How do I add a different year tax return

[DoninGA]

The TurboTax online editions are only for tax year 2019

To complete and file a prior year tax return, 2018 thru 2016, you would need to purchase, download and install on a personal computer one of the desktop editions for each year required from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/