You CAN file your 2020 amended return electronically. See the TurboTax FAQ I'm linking below to amend your return. Follow the instructions carefully, as they are quite specific.
How do I amend my 2020 return?
*** I am NOT a tax expert. I am a seasoned TurboTax user, and volunteer to provide assistance to TT users. Nothing I post is to be considered TAX ADVICE; I bear no legal liability for responses.***
