Can I claim BAS and BAH as nontaxable income or is that already figured in to what Is taxed on my W-2?

You do not make any adjustments to your active duty W-2 to account for BAH and BAS.  Enter your W-2 as is.

BAS and BAH are tax exempt allowances, so not taxable to you as income. Your W-2 reflects the portion of your taxable military wages in Box 1.  Your W-2 will also reflect if you receive non-taxable combat pay at any point during the year (Box 12, Code Q).  

PA state tax return has a section on nontaxable military income.  Am I supposed to input the BAH/BAS that I received while living in PA? I am a nonresident of PA.