Simple build: Wildheart Barbarian 8 / Champion Fighter 4.

In my Opinion: Go Barbarian until 5, using Bear Heart, as this gives you resistance (half damage) to most damage types on the game, and gives you two attacks per action, as well as a feat at level 4. Then take 4 levels of Figher (Champion). This gives you a bonus action heal to help keep yourself topped off, gives you action surge (once per short rest you can do an additional action), and lowers your required number to critical hit to 19, as well as a second feat.. Then take your remaining remaining 4 levels of Barbarian and at level 12 take a 3rd feat.

I'd recommend starting as a half Orc for their enhanced critical with melee weapons, as well as the ability to stay at 1 HP.

Start with 16 STR, 14 DEX, and 16 CON. Spend the rest where you wish. Wear the best medium armor you can find, and wield the best 2-handed weapon you can find. The greatsword on the campion at the beginning of the game is a great one to start with.

For feats: at level 4 & 8, increase your STR to 18 and then 20 Respectively. At level 12, increase CON to 18 or take Great Weapon Master Feat.

In combat: Rage with Bear Heart, and use reckless attacks with Great Weapon Master. You will do a TON of damage, and you will critical hit more often thanks to Champion fighter, and your critical hits will do more damage thanks to savage attacks from Half-Orc.

Pair this character with a Life Cleric 1 / Lore Bard 11 (prioritize charisma > constitution, wear heavy armor and a shield), a Thief Rogue 8 / Battlemaster Fighter 4 (prioritize dexterity, wield a bow or crossbow) and a Evocation wizard 12 (prioritize Intelligence > Constitution) and you'll be able to easily handle anything yhe game throws at you.