You do not add your 2016 Form W-2 to your 2017 tax return. You will need to file a separate return to report that income if you did not file an income tax return for 2016.
You can only use Turbotax Online to file for the current year (2017) taxes, and not for any other year.
If you would like to use TurboTax for 2014, 2015, or 2016 you will need to purchase the Desktop Version for the specific year for which you need to file a return. You can purchase the Desktop version at this link:
You are also able to download the Forms and Instructions free from the IRS web site at this link: