If you e-filed the 2020 tax return you would have received an email from TurboTax when the IRS either Accepted or Rejected the federal tax return. Look in your email account for a TurboTax email from sometime between January and October 2021.
There also will be an Electronic Postmark report in the PDF download of the 2020 tax return if you used the TurboTax online editions for 2020 to e-file the tax return. In the report will be the date/time the tax return was e-filed and the date it was Accepted by the IRS, if Accepted.
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 2023 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 and Click on Download/print return (PDF)
To check the status of an e-filed return, open up your desktop product or log into your TurboTax Online Account. You can find your status within the TurboTax product.