For code there's a ton of free tutorials on youtube, you can pick an engine and practice a bit prior. Godot is very good for beginners and pretty intuitive, the community is super helpful too. It doesn't have to be an AAA level project after all, make something really simple! Don't be intimidated, that's how a lot of us learned. :)
Plus you can find a team and help them by playtesting for bugs, balance, or search for some missing assets like sound effects, music or sprites, just make sure to check the license. Or maybe even try writing for games or making VFX or designing UI?
Jams are a good place to learn new skills, good luck and don't get discouraged!