If you are not a resident alien with a green card or ITIN, then you flat out can not use TurboTax to complete a U.S. tax return. You have a file a 1040-NR which TurboTax does not include or support. To complete a 1040-NR online you'll have to use www.sprintax.com
EXACTLY how long have you been in the United States? That may determine what you need to file. Be as details as possible about the dates you were in the United States and if you had any other kinds of visas.