No. Once you have gone into the "Amended Return" mode, just go through and make the correct entries where you normally would. TurboTax will take care of transferring the original amounts, the new amounts (you just added), and calculating the net change.
For more information on amending a return, please see this FAQ:
https://ttlc.intuit.com/replies/7276601
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"