Multiple Choice Field in a Form

Hello, I'm a beginner and I'm looking for some help because I'm really stuck trying to solve a problem.

I need a field on a form to perform multiple selection. Basically something that functions like the Choice field type but with the possibility of choosing more than one option.

Furthermore, I need to create more than one of this kind of field and make them depedent on the others that come before.

Hope you can help me, thanks.