After you file

See this TurboTax support FAQ for amending a prior year tax return - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-change-correct-return-a...

To access your prior year online tax returns sign onto the TurboTax website with the User ID you used to create the account - https://myturbotax.intuit.com/

Start the 2024 online tax return by entering some personal information then click on Tax Home on the left side of the screen.

On the Tax Home webpage -

Scroll down to the section Your tax returns & documents.  Click on the Year 2023 and Click on Amend (change) 2023 return