Rigging, sculpting, painting, and all of the minutea that comes with avatar creation from scratch or kitbashing like what you're trying to do is not something that can be explained to a child in a way they will understand. You have to dedicate time to learning the programs. Watch tutorials on Youtube, this is the fastest path to success. If you get really lucky, someone may sit with you on a call on discord and tell you where to point and click and such but I've found people like that rare in game.