You need to trigger the 1040X to be produced and populate the numbers shown on the original return.  As a best practice and to avoid being charged for the 1040X separately, you should make a copy of the original return and use the original to amend the return.

See this article for detailed instructions: https://proconnect.intuit.com/community/help-articles/help/how-to-amend-an-individual-return-1040x-o...