Amended return

I amended my 2020 return because I forgot to enter my 2019 refund that was applied to my 2020 tax estimate.  It resulted in my refund going from $0 to $3692 yet when I get to the end... it says it did not detect any changes in my return (yet the refund number did change).  Also, now that I will be getting a return, I would like to add my bank account information but wondering where I can do that on this amended return?