How can I add my montanag state taxes that were. With r d on my w-2?

If  you are saying you have Montana state taxes withheld on your W-2, then enter those amounts in your W-2 in the state taxes section. If you lived and worked in Montana the entire year, file only a Montana return as a full year resident.

Montana Filing Requirements (click for more details)

You must file a Montana Individual Income Tax return if:

• You were a resident or part-year resident of Montana, or
• You were a nonresident who received Montana source income, and
• Your federal gross income, excluding unemployment compensation, meets the Montana filing threshold.

You should file a return if you had Montana tax withheld from your paycheck or if you paid estimated income tax, even if you aren't required to file a return.

If you have more questions, please add any other details so we can be specific to your situation. See the image below.

i.e..............you enter those MT income wages and MT taxes withheld $$ on the W-2 form that you put in, in the Federal section of the software.  Those $$ will be automatically applied to the MT forms when you eventually get to the MT software AFTER the Fed forms are fully filled in.