military question for the GF or wife's

I've reconnected with this guy recently. I've known for 6 years. We've always said our hellos here and there but we are trying to see where it goes...
Well, he was once in the marines, but he's planning to join army...he's currently waiting for them to send over his marines paperwork to the army and once that happens they'll either be sending him to Korea, Germany, or Hawaii 3-4 years.
He wants me to go....but also mentioned marriage...
Do you HAVE to get married in order to go with?
How does this work
Thank you:)