Without Information which Game etc we can't help lol.
When you find dlls in assets/bin/data/managed, then mod the dlls.
When you find global-metadata in assets/bin/data/managed, then mod il2cpp.so
When you find nothing in assets/bin/data/managed, then take a look into the lib Folder.
Or the Game needs smali/xml modding.
Or it is based on .lua ( but thats really rare, never saw a Game which is only based on Lua. )