Marrying with a man from US army?

Not enough information to give a specific answer. There are a lot of variables which can be factored in here. For a US citizen to marry a US soldier, it's no more difficult a process than marrying a civilian. For a foreign national to marry a US soldier, it gets a bit more complicated.

If the two of you are considering getting married, he needs to speak with his Chain of Command, and possibly the Battalion Chaplain, who would be better equipped to advise the both of you on the procedures necessary to make it as seamless a process as possible, whatever the specifics of your situation may be.