If you used the desktop CD/Download editions installed on your computer, the only copy of your tax data file and any PDF's will be on the computer where the return was created. TurboTax does not store online any returns completed using the desktop editions.
A 2020 tax return can be completed without transferring the 2019 tax data. However, you will need to know the 2019 AGI to e-file the 2020 tax return.
Go to this IRS website for free federal tax return transcripts - https://www.irs.gov/individuals/get-transcript