If you are considered a nonresident of the US, you should file a 1040-NR which TurboTax does not support. If you need to prepare a 1040-NR, you can use Sprintax which is a partner of TurboTax. Just click on the link; the process is similar to what you did on TurboTax.
Tax Tips for Resident and Non-Resident Aliens
Please view this short video that can help you determine your status.