TurboTax does not support tax years prior to 2016.
You can either go to a tax professional in your local area for assistance or use the IRS website for prior year federal tax forms, schedules and instructions - https://apps.irs.gov/app/picklist/list/priorFormPublication.html
To complete prior year tax returns, 2016 thru 2018, using TurboTax you will need to purchase, download and install on a personal computer one of the desktop editions for each tax year required from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/
Prior year tax returns can only be printed and mailed, they cannot be e-filed. Use separate envelopes for each tax year when mailing the tax returns.
When you have only W-2s, the easiest and cheapest way to prepare and file tax returns for each year is to download the blank forms from the IRS and fill time out and mail them in with a copy of the W-2. You should mail each year in a separate mailing envelope. Here is where to find them to download: https://www.irs.gov/forms-pubs/prior-year
You could buy and download a program and install it on your computer for each year for 2016, 2017 and 2018 using TurboTax. See here: https://turbotax.intuit.com/personal-taxes/past-years-products/
All of these returns must be printed and mailed. They can't be efiled. You can still get a refund from all 3 of these years but the 2016 return must be filed by July 15 to get a refund.
TurboTax no longer has software available for 2013, 2014, and 2015. It is too late to file those years for a refund. You are required to file them however, if you owe taxes.