You can use the steps here below to file a 2016 return using TurboTax CD/Download software.
NOTE: It would need to be prepared, printed and mailed. You cannot e-file a prior year return. And it cannot be done online. Online is for 2017 tax year only.
The other option would be to download the Forms and Instructions, free, from the IRS website at this link https://www.irs.gov/forms-pubs complete them by hand and mail to them.
How do I file a prior year tax return?