Could I create a Form Builder that will allow me to subscribe many users that depend on a parent user?

Let me explain this better, I would like to make a subscription of an event, where I can invite many people, these guests must be registered and I want to show that they are dependent of my person without the need to transcribe it. Do you understand what I mean?

Is there any way to save a variable and keep it constant for the following fillings of the form?

Finally, a solution where it tells me, do you want to invite another person? and that a new form item is displayed to add the information. is it possible?

This idea is blowing my mind and I don't have a solution with SP Builder at the moment. Any way to fix this?