I recieved a 1098-T form for 2016 but I wasnt school for 2016, only for 2017. What do I do?

SAVE IT.

The 1098-T reports what was billed in 2016. I assume you were billed in December 2016 for classes you started in January, February, or March of 2017, but you did not pay for the classes until 2017.

You would have reported what you paid in 2016 if you were applying for a credit. Since you are not applying for a credit for 2016, because you didn't pay any education expense, you can enter the information into TurboTax, but you will need to click on the drop down "This is not what I paid" when you enter the information from Box 1 and/or 2 of the 1098-T and enter 0 so that the software knows you didn't pay and does not calculate a credit.

If you received a scholarship or grant that paid the school in December, you do have to enter it.

If there was no payments made by you or for you, you could disregard reporting the 2016 1098-T, but save it and compare it to the 1098-T you get for 2017. Next year the school will  need to report what you paid, so it should be more clear.

When a school bills in December for classes starting in January, February, or March, you have the option to pay (and claim the amount paid) in either December or pay (and claim) the following year.