I didn't file my 2019 taxes can I file them now and then file my 2020 separate and how will I do it

[DoninGA]

To complete and file a 2019 tax return using TurboTax you would need to purchase, download and install on a personal computer one of the 2019 desktop editions from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/

A 2019 tax return can only be printed and mailed, it cannot be e-filed.

[Ray in Bowie]

Check the web (Amazon; Google Shopping, etc.) and see if you can get a better price on TT 2019 software.
Don't just check the main TT website.
And the prior answer was correct. Unfortunately you need to mail in old returns; you cannot e-file.