The Boss Fight in this game

Took me a moment to figure out which boss fight you were referring to... But I think, from your description, you're talking about the Demolisher in The Pit.

its near impossible to do unless your willing to just use the two explosives then call it whack a mountain do legit no dmg with the shit weapons lying around

First of all, there should be a halfway-decent machete in the pit with you. You'll definitely want to use that instead of the random junk you'll find scattered around the area.

Now, this fight plays out like an old-school Zelda boss battle... Where it's less about the damage output and more about finding the right pattern. Namely, you need to get the boss to stun himself.

You should notice that the Demolisher likes to charge at you. And if he runs into something, he'll stun himself. So you want to stand in front of something big and solid (like the concrete pillars, or the containers) and wait for him to charge, then dodge out of the way. When he runs into the object, he'll be stunned for a couple seconds. And you're free to pound away at him.

Now, yeah, he's got a lot of health. And those propane tanks can be useful in speeding up the process. But once you've got the pattern down, you should be able to carve him up without taking any damage.

Also - If you've taken the right skills, thrown weapons do bonus damage. So chucking the machete at the demolisher will speed things up, while also giving you a little more safety... But it can also make the random junk scattered around the area halfway-useful.

IM EXTREMELY upset at techland for not thinking through with this fight lol its a joke

It's supposed to be challenging. Rais is trying to kill you. You've been dumped, unarmed, into a pit full of zombies, and then had a big ol' demolisher thrown in. You're not supposed to be able to just chop that thing up. Standing toe-to-toe with it is going to be suicide. You need to out-maneuver it.

Yeah, it's challenging. But, honestly... Once I got the pattern down and started dodging all his attacks, I felt like a badass. It was a tremendous feeling of accomplishment when I finally killed that guy with nothing but a machete and some garbage.