To access your current or prior year tax returns sign onto the TurboTax website with the User ID you used to create the account - https://myturbotax.intuit.com/
Scroll down to the section Your tax returns & documents. Click on the Year and Click on Download/print return (PDF)
A 2020 tax return can only be printed and mailed, it cannot be e-filed.
Print, sign, date and mail the tax return to the IRS. Include with the mailed return any forms W-2 and 1099 which have taxes withheld. Go to this IRS website for mailing addresses - https://www.irs.gov/filing/where-to-file-paper-tax-returns-with-or-without-a-payment
There are no penalties for filing a tax return after the due date if filing for a tax refund or there are no taxes owed.
If the return in the PDF file you can access needs to be changed in anyway before filing ... you can either make the changes on the printed forms or use the downloaded 2020 program.
If you started your 2018 - 2020 return in TurboTax Online but weren't able to file it before the shutdown, you can finish and paper-file it in the TurboTax download software for PC or Mac.
See this TurboTax help article:
https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-finish-a-prior-year-return-that-i-...