TurboTax does not support tax years 2016, 2017 or 2018. When filing those tax years for a refund, the refund will not be paid since it is beyond the 3 year limit from the due date of the return.
If you have taxes owed from those tax years then you should seek out a local tax professional to assist you in completing those return since penalties and interest continues to accrue until the taxes are paid.
For tax year 2019 thru 2021 using TurboTax you would need to purchase, download and install on a personal computer one of the desktop editions for each tax year from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/
A prior year tax return can only be printed and mailed, it cannot be e-filed using TurboTax. When mailing multiple tax years use a separate envelope for each year. You should also use a tracking service from the US Post Office so that you know the tax returns have been received.
