Were you finished with 2020? If you finished it but didn't file you can just print it out and mail the pages you need to file.
If you still need to finish,
Start a 2021 tax return using the User ID for the 2020 online tax return. Once your personal information is entered the prior year tax returns will be available on the Tax Home web page.
You have to print and mail prior year returns. When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS received the return. Don’t forget state. Mail each year and state in separate envelopes.
You will need to download the .tax2020 file from online and switch to the Desktop program to finish. You need to use a full Windows or Mac computer. And mail the return. If you paid for the Online version ask support to give you the Desktop program download.
How to finish a prior year online return
https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-finish-a-prior-year-return-that-i-...
After you get the program installed the first thing to do before you open your tax return .tax file is to update the program and install any state programs you had. Then open your file. So you first might need to start a fake return to be able to download the state program (go to FILE - NEW).
