gillcristmark:
I assume you used the 2020 desktop software for your return last year. Most importantly, are you sure you have the *.tax2020 data file from last year and know its location?
sandy4042 is correct above. It doesn't perform the 2020 data transfer as part of the installation process. After the program is fully launched and you arrive at the main screen, you have to actively start a new 2021 return first. Maybe you did that, but we don't know for sure.
I don't know if you're using the Windows or Mac version. This is what happens with the Windows version:
After installation, and once the TurboTax GUI opens to its main screen, and when you choose to start a new 2021 return, the software churns and searches through your computer for any *.tax2020 data files. If it finds it, it displays a blue button "Transfer Return" to transfer-in the data (it may find more than 1 if you have more than 1.) If it doesn't find it automatically, there is a Browse button in the lower left that brings up an Explorer file directory popup, where you can tell TurboTax where the *.tax2020 data file is located.
If the automatic search or the "Browse" method is not letting you transfer the *.tax2020 data file, you'd need to explain more about the roadblock you are encountering and whether or not you have the *.tax2020 data file on your computer.
