Can I save a copy of 2016 tax returns?

Yes, to save follow this steps:

1. Open your return in TurboTax.
2. Click the File tab.
3. Choose any of these options Save/Save as (.tax20** file) or Save to PDF (for .pdf file).
   
4. In the pop-up, you can change the name and location of the file.
5. Click Save.

Following this thread. I

Yes, to save follow this steps:

1. I opened myTurbo Tax for a Tax2022.tax2022 member
2. Clicked the File tab.
3. Choose Save as  
4. In the pop-up, changed the name and location of the file and Clicked Save to  of Tax2021.tax2021 to disk
5. I closed and re-opened TurboTax and selected Tax2021.tax2021
6. It read it in but it referred to it as a 2022 Return. I need it for 2021.

    What more do I need to do?

   thanks

@DaveMiha2304   Your post is hard to follow.  You can't change a 2022 return ending in .tax2022 to be a 2021 return.  Are you trying to do a 2021 return?  You need to have the 2021 program installed.   Did you buy 2021?
https://turbotax.intuit.com/personal-taxes/past-years-products/