If you didn't file a 2016 return you do not amend it. You just finish and mail the original return.
How do I finish a prior-year return that I started in TurboTax Online?
https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-finish-a-prior-year-return-that-i-...
You can only buy the download for prior years. You have to buy a separate program for each year. They only sell the last 3 years. You need a full Windows or Mac computer to install it on. You can buy any version. All the Desktop programs have the same forms. You just get more help and guidance in the higher versions. Buy the download here
https://turbotax.intuit.com/personal-taxes/past-years-products/2016
If you have a simple return, you can fill out the blank forms by hand for free.
Here are some blank forms & instructions for 2016
1040 https://www.irs.gov/pub/irs-prior/f1040--2016.pdf
Instructions https://www.irs.gov/pub/irs-prior/i1040gi--2016.pdf
1040A https://www.irs.gov/pub/irs-prior/f1040a--2016.pdf
Instructions https://www.irs.gov/pub/irs-prior/i1040a--2016.pdf
1040EZ https://www.irs.gov/pub/irs-prior/f1040ez--2016.pdf
Instructions https://www.irs.gov/pub/irs-prior/i1040ez--2016.pdf
2016 Tax Tables https://www.irs.gov/pub/irs-prior/i1040tt--2016.pdf
Publication 17 Tax Guide for 2016 https://www.irs.gov/pub/irs-prior/p17--2016.pdf
Prior year returns can only be printed and mailed. When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS received the return.
And don't forget state.
