for 1.20.4 it keeps crashing when i try to start the game:

The game crashed whilst initializing game
Error: java.lang.RuntimeException: Could not execute entrypoint stage 'main' due to errors, provided by 'whereisit'! Exit code:-1

how do i fix it?

can you post the full crash report? should be under crash-reports in your game directory

crash-2024-01-07_10.42.15-client.txt

Update YACL, you have the 1.20.2 version installed: https://modrinth.com/mod/yacl/version/3.3.1+1.20.4-fabric