How can I prepopulate one form with data that has been previously entered in another form, in same application?

How can I prepopulate one form with data that has been previously entered in another form, in same application?

I am looking in  https://kbase.creator.zoho.com/records/populate-one-form-with-data-from-another-form

But I could not make it work :-(

On my application (which I am trying to build) is like that:

There is a Form "Registration" and 3 fields (Number; Name; Email)
There is a From "Feedback" and 3 fields (Number; Email; Comments)

So, every time that the customer put his Number on "Feedback" form, I want his email to be automatic updated.

Could you make an exemple to me?
Thanks!!!