Boyfriend joining the military soon

My boyfriend is planning to join the military in a little over a year. He’s 18, and doesn’t know what he wants to do, and has been considering the military for awhile. He doesn’t know what branch but has mentioned Air Force.

What can I expect as a girlfriend? I don’t think he’s choosing a job where he’d be in terrible danger all the time, but I still worry.

Another question, he has a lot of self harm scars on his arms and I’ve heard they’ll accept those with mental health issues now. Is this true?

Any advice is welcome.