If you are a nonresident, you should be filing a nonresident US tax return.
TurboTax does not support nonresident returns.
However we have a partnership with Sprintax offering a
nonresident tax filing solution to our TurboTax customers.
Visit
the TurboTax/Sprintax site for more info or to get started.
Also, your SS benefits may be treaty exempt. Check with Sprintax.