u/Vihatas

I want to make a character who can change between three classes in the middle of the fight and have their moveset change with it. I've figured out how to change the class; the issue is that they retain skills from the other classes instead of only having access to class-specific skills. How do I make it so that when they change from class A to class B, they only have access to class B's skills and only regain the other skills once they swap back to class A?

Also, how do I make it so that the levels of all these classes are the same so the player doesn't have to grind them individually?