What years? Are you using the 2020 Desktop program and have the .tax2019 file? Just start a new return, go to FILE - NEW and the first thing it should do it look for any .tax2019 files on your computer and ask if you want to transfer from it. If it doesn't find it you can browse to where it is. You can only transfer at the very beginning. So if you already started 2020 you need to start over with a New Return.
Are you using Windows or Mac?
https://ttlc.intuit.com/community/entering-importing/help/transfer-last-year-s-return-to-turbotax-fo...
