I tried changing versions and everything. I am currently set to the Slightly_Vanilla_Flavoured-2.3.0 version.
crash-2021-06-02_13.32.25-fml.txt

Hello! It seems that your modpack is modified, and the Client Tweaks mod is causing issues.

Hello! It seems that your modpack is modified, and the Client Tweaks mod is causing issues.

I have tried to reinstall multiple times even to new profiles and it does the same thing.