Oh hell yeah I can absolutely do this with you!
I'm not a GREAT artist/composer but I most certainly can do it. I make my games in godot.
...I think the best way to do this would be that you make the game and tell me what art/music/sound effect assets you need, then I make the assets and send them to you. We should also definitely talk about the design and theme of the game beforehand and during the process. No idea how I would edit the same godot project you're working on lmao, but if you know, we can also try that