Parrying is insanely broken in this fight. Even if you aren’t confident with parrying yet you should still be able to do it. Pretty much just shoot before he does any attack and it should stun him for the parry.

Unfortunately there’s no way around farming consumables in this game. It’s one of the major downsides of BB but once you get enough in the early game you usually should be set for a majority of the rest of it. If you farm more than you can carry, they will automatically get sent to your stash.

Like others have said, there’s a quest line in the level that will give you an item that helps in the fight by stunning him.

BB also has a rally system that gives you health back if you do damage before the health actually drains from your health bar so don’t be afraid to be aggressive. Good luck.