The instructions on the site tell me to "2. Scroll down to Your returns and documents (you may need to select Show)." None of that is on the screen when I log in.

These instructions sound like downloading a PDF, but would be for TurboTax Online.

If you are using TurboTax CD/Download, then follow these instructions, instead:

In TurboTax CD/Download,

• get the PDF by finding the .tax file for the year you need on your computer (.tax 2019 or .tax 2020, for example) or 
• opening the same year for the software.
  • If you need to open the software, go to the upper right corner to Print Center to view or print the PDF.
  • For more information, see: How do I save my return as a PDF in the TurboTax software for Windows?

What are you trying to get?  Have you already filed?  Are you using the Online browser version or the Desktop CD/Download program?  

Are you trying to get back into an online return?  For Online, Click on Add a State to let you back into your return.

From Tax Home (the first screen you see after you sign in), scroll down to Your tax returns & documents. You may have to select Show to open the drop down.

Select 2020, and then select Add a State (you're not actually adding a state, this is just the workaround).