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.
if you don't want to pay to purchase the Turbotax 2019 app, you can prepare your return manually. tax forms are available for download from IRS website
If you want to file for free you can fill out the forms by hand. Here are some basic forms…..
Here is the IRS 2019 Form 1040
https://www.irs.gov/pub/irs-prior/f1040--2019.pdf
or if you want bigger type use 1040SR for Seniors,
https://www.irs.gov/pub/irs-prior/f1040s--2019.pdf
And 2019 Instructions https://www.irs.gov/pub/irs-prior/i1040gi--2019.pdf
2019 Tax and EIC Tables
https://www.irs.gov/pub/irs-prior/i1040tt--2019.pdf
Sch 1 : https://www.irs.gov/pub/irs-prior/f1040s1--2019.pdf
Sch 2 : https://www.irs.gov/pub/irs-prior/f1040s2--2019.pdf
Sch 3 : https://www.irs.gov/pub/irs-prior/f1040s3--2019.pdf