What are you doing??? Are you needing to prepare a 2021 return that you never filed? Or are you not sure if you filed one 3 years ago?? You need to explain your situation so that, hopefully, someone can understand how to comment. And what does 2020 have to do with it?
Online TurboTax is only for 2024 returns. If you need to prepare and file a 2021 return, that has to be done in 2021 desktop software and cannot be efiled. I hope you're not trying to prepare a 2021 return in Online TurboTax--that's a no-no!!
If you explain, someone may be able to help you.