Updating form input fields in real-time

This related post from @Chem I found very useful:

Run basic math in real time on a form using JavaScript

but I’d like to know if it’s possible to update input fields on the form in real-time?

I’d like to obtain the text value of the dropdown and instantly present that in the field below so that it could be edit.

Vidyard Recording?

many thanks for your consideration and any ideas you may have.