That sounds interesting. I haven't coded many 3D games before, so I don't think I can help develop it, but I have lots of experience with 2D game design, if you want to learn how to code 2D or just learn the basics of game design.
I'd recommend trying Micro Studio if you're interested, but if you want to learn 3D, then just a heads up, Unity probably wouldn't be the best to learn without experience.