How to file a non-resident tax return with W2 and W2C? My employer initially issued an incorrect W2 (holding Social security and Medicare taxes which aren't applicable)

[JulieCo]

You mention a non-resident return.  TurboTax does not support 1040NR returns but has a partnership with Sprintax for preparing 1040NR returns.

https://ttlc.intuit.com/replies/4028799

In general though, regarding a corrected W-2 form, you will only want to enter the W-2C information as that is the corrected W-2.  If you had already entered the original W-2, go back to that entry and then make the corrections per the W-2C form.

https://ttlc.intuit.com/replies/4192512

If you have already filed your tax return, then you will need to file an amended return to make the W-2C correction.

https://ttlc.intuit.com/replies/3288565