What is the correct way to make an interaction between two BoxTitles?

Question

Python

Hello, I am creating a text game in python using npyscreen. There was such problem:

I create two boxes BoxTitle, before redefining them in separate classes. And in the second box there are multiple choices (MultiLineAction). Is there some method to somehow interact with the selected element. For example, by pressing the Enter key on the selected element, move this element to the main (top) box? I will be very grateful for your help.