This task is somewhat complicated, but not impossible, especially if you file electronically.
First, you need to get his tax data, probably only his military W-2. With that, prepare the federal return jointly.
You will need to prepare the Maryland return jointly, but unless your husband is a legal resident of the state of Maryland (he has designated Maryland his domicile state with the military), his military pay will NOT be taxed on the Maryland return. It WILL be reported on the return and probably used to raise your tax rates, but the actual military salary will NOT be subject to Maryland income taxes.
If your husband has a domicile state (other than Maryland) that has a state income tax, then, more than likely, he will have to file a state income tax return for his domicile state. Whether he has to pay taxes depends on the state tax laws for that state.
If you want professional help to do this, I prepare returns like this as a matter of routine. You can contact me at email@example.com