These class descriptions are meant for informative purposes and you can, of course, use your imagination in any way that you would like as you build and progress your character.
The barbarian is the best class for beginning players in my opinion. One of the main reasons for this is that it is the optimal class for someone that wants to play but is a bit skeptical regarding participating in the roleplaying portion of DnD. I know that sounds strange, but a lot of new players are terrified of participating in the conversations and roleplaying interactions. I believe this is the primary thing scaring new players away. Remember, the average person is more terrified of being up on stage in the limelight than death itself. That and the stigma that we are all nerds. Which we are. Accept it and move on.
Another big reason why barbarians are great for new players is because they are extremely difficult to kill and quite a simple class to play. You have a magnificently large health pool and not a lot of bells and whistles; however, the bells and whistles give you some action economy concerns and teach you how to manage your limited resources. Speaking of limited resources, though, building a barbarian is going to make you run into that concept right out the gate. They are multiple attribute dependent (MAD). You need Constitution, Strength and Dexterity, which is why you lose out almost entirely on roleplaying. You will likely have no sparkle in your personality, you will be dumb as a box of rocks, and you couldn't make a wise decision if you rolled at advantage.
With all of this being said, there is really only one world shaking path. The rest will not gimp you, however, and most of them are quite flavorful.
6: Path of the Berserker
Pick this if you are a short tempered Italian man (like myself) or you like the idea of being useless outside of combat.
I may get some heat for this one, but such is life. You already get rage as a base barbarian which is pretty amazing in terms of damage mitigation. I do not see the value of frenzy on top of this. The trade off just lands you in a very dull situation when it comes to non-combat situations. You suffer much more dearly from a roleplaying perspective with your level of exhaustion that you gain from frenzy. With a level of exhaustion you will roll all non combat skill checks, including initiative, at disadvantage. With your second level you will lose half your movement speed, where advances in movement speed are a barbarian's innate perk.
Yes, you get an extra attack in on each of your turns as a bonus action, but that is not particularly impressive. Mostly because all you functionally gain is your damage bonus. If you really want a damage bonus when you swing an off-hand weapon, just take the Dual Wielder feat. Mindless Rage is valuable because nobody wants to be charmed or frightened, but Intimidating Presence is worse than useless in my opinion. It requires you to spend an entire action to maintain the single enemy's fear of you. Just go kill it instead. You're bred and raised for war!
This is the only path I would honestly never take.
5: Path of the Storm Herald
Play this if you want to feel like you're casting spells but you don't want to deal with managing them.
The Storm Herald is a fantastic concept from a roleplaying perspective. It also adds quite a bit of potential depth to the character leveling process since you get to change your Storm Aura each time you level, if you would like. Thankfully, the saving throws against your Desert, Sea or Tundra effects are based upon your Con modifier which should be quite large. At level 3 Desert deals nominal fire damage to all other creatures around you; Sea deals some extra lightning damage to a single enemy; Tundra allows you to grant some temporary hit points to your friends. None of these are world shaking but they are all helpful.
Storm Soul at level 6 grants you some addition benefits. Desert gives you resistance to fire damage and you can touch random things to start them on fire; Sea gives you a swimming speed, the ability to breath under water and resistance to lightning damage; Tundra gives you resistance to cold damage and you can turn water into ice for a minute. None of these are as interesting as what you get at level 3 so far as I am concerned, but they do not harm you either. At level 10 you can extend the damage resistance that you gained at level 6 to your party members which is actually quite powerful.
4: Path of the Battlerager
Pick this if you are a dwarf and you want to pretend you are Shredder from Ninja Turtles.
I personally love this path and because of that I really want to rank it higher. The reality, though, is that only being available for dwarves is a painful limitation. If your DM allows you to take this as any race I would put it at number 2. Battlerager Armor, which allows you to wear spiked armor and attack with it. Spiked armor has a base AC of 14, allows you to add +2 based upon Dex, and lets you still use a shield. That means from level 3 onward with 14 Dex and a shield you can have 18 armor class.
Yes, you get to wear amazing looking, very effective armor and you get to hit people with it for free as a bonus action every round, dealing 1d4+ your strength modifier. Speaking of that strength modifier, you get to raise that quite a bit. Now that you do not need a Dex higher than 14 for Unarmored Defense you can focus more on Con and Str. Beyond this, Reckless Abandon and Battlerager Charge are functional but nowhere near as interesting. Some extra temporary hit points and the ability to dash as a bonus action are neat, but not impressive.
You also get to hurt people while hugging (grappling) them which I find to be wildly amusing.
3: Path of the Ancestral Guardian
Play this if you want your party to like you more and not judge you as much for being a big dummy.
This path turns you into a much more valuable party member and turns your tanky barbarian into a party helper. Strangely, nothing in this path helps you deal more damage which is traditionally considered to be your purpose as a barbarian. Ancestral Protectors at level 3 allows you to force a target to attack your party members at disadvantage, and when they do attack them it is at disadvantage, which can effectively turn a boss battle into a cakewalk. It will functionally force something to just attack you. It has much less return in any combat that has multiple enemies, though.
Spirit Shield at level 6 lets you directly mitigate damage to your party members. Anyone that you can see within 30 feet gets the damage that they have taken reduced by 2d6 if you are raging. This goes up again at levels 10 and 14. You also gain the ability to use the spell augury for free which is a fascinating addition to a melee class and can add a ton of flavor to your campaign. Vengeful Ancestors just allows you to flat out deal damage while simultaneously protecting your companions, which is icing on the cake.
2: Path of the Zealot
Choose this if you want to pretend you are an uneducated Crusader.
The idea of just ripping through battle in the name of your god or goddess, but not really needing to do all the worshipping stuff sounds pretty amazing. That is what this path is built for. You automatically deal an extra 1d6+ half your barbarian level on each of your attacks while you are raging. This damage is also radiant or necrotic, so it bypasses physical resistances. The Warrior of the Gods perk is mostly useless, but it does not weigh the path down.
With fanatical focus you get to reroll a single failed saving throw every time you rage. The power of this should not be underestimated as there are a number of spells that can take you entirely out of combat, make you fight your party, or deal a horrifying amount of damage to you. If you can reset that you just took a step toward being unstoppable. Zealous Presence is fantastic if your party finds itself in a tough spot or if you just want to cheese it in a boss battle. Anyone of your choice within 60 feet, up to 10 creatures, gets advantage on attack rolls and saving throws until the start of your next turn. Just because of your guttural roar in the middle of combat. At level 14 you can just shrug off fatal blows and you do not go unconscious until your rage ends which is unfathomably amazing.
1: Path of the Totem Warrior
Play this if you want to jump into the middle of a horde of enemies and never die.
You're functionally Minsc with his pet hamster Boo, who should have been a barbarian and not a ranger. That is a discussion for a later day, though. You have an innate attunement to nature and can cast beast sense and speak with animals as rituals, so functionally for free. I buried the lead with that first statement. This path is the ultimate meat shield. No questions asked in my opinion when it comes to an ability to stand in a spot and soak up damage there is no competition.
You already have resistance to bludgeoning, piercing and slashing damage when you rage as a barbarian, but at level 3 as a Totem Warrior you can take the Bear totem as your Totem Spirit. This gives you resistance to all damage types except psychic. You just stand there with your absurd health pool and only take half damage. Yes, you can also take the totem of the Eagle, the Elk, the Tiger or the Wolf but it's a tough argument. Wolf is pretty amazing in its own right since it grants your friends advantage on melee attack rolls against any creature within 5 feet of you. While this sounds incredible, just look at Bear totem again and you'll see why it pales in comparison.
At level 6 you gain the Aspect of the Beast which allows you to call upon another animal totem, which can actually be different from your level 3 totem. Most of these are lackluster in comparison to what you get with your Totem Spirit; however, they do add quite a bit of flavor and utility to your character. Nothing here specifically jumps out as being overwhelming compared to the others, but they each have their benefits. Honestly, if you only got Totem Spirit you would be fine.
You also gain the ability to cast commune with nature for free, so you're even more of a hippie now. Ironic, given that you are absurdly violent. A tree hugging, animal loving whirlwind of death. Totemic Atunement at level 14 provides you with another expansion on top of your two previous totems. These are much more powerful and interesting than what you received at 6th level variously allowing you to fly, rush through enemies and knock them down, simply knock down enemies when you hit them, cause enemies to have disadvantage while attacking those next to you or make extra attacks.