You will need to enter this information in the "My Info" section.
Also, any wages not taxable for being ion a Combat zone, are noted on your W-2, and recorded when you enter that W-2 form in the tax software
The amount the Military claims is not taxable is shown and entered in box 12 of the W-2, with a code Q beside the $$ amount.
Box 1 of the W-2 should also be lower than box 6 on the W-2 by at least that code Q amount (maybe more due to other pre-tax deductions from pay)).
IF you don't have any code Q $$ in box 12, then you need to talk to your Payroll people for correction...or an explanation of why it's not there.