HELP!! I think my world is corrupted!

TLDR:
My game crashed and continues to crash when I play on the world for more than 30 seconds, as well as crashing when I try to make a world backup.

The Story:
So l've been playing modded mc on this world for about a month with no issues. Yesterday, I entered the nether and my game started stuttering before it stopped responding and gave me this exit code (-805306369). The official page for it says that it's a bug for a completely different version of the game, 1.16.3 or something like that, so that wasn't much help. Whenever I try to play on the world it crashes after about 30 seconds, and if I try to make a world backup it crashes immediately. It does make a back up, but the back up folder it creates also seems to be bugged as it can't open like the other backup files l've made. I understand the more mods you play with, the more you run the risk of something like this happening. I'm curious if anyone has any ideas for a solution to get my world back.

Context:
I have a high end pc, and l've allocated 20 gigs to mc because the exit code said it could need more, but that didn't work and it was running on 14 before. The version I'm running is 1.20.4 and I have about 150 fabric mods installed that haven't had issues before. I have pretty much every optimization mod. It's also fairly important to note l'm using the BetterNether mod since it started when I entered nether for the first time and crashes faster when I’m in the nether.