all my comments are based on friends being in the military. Three of the guys I grew up with went into the service. I also know a couple more from work who are reservists.
He’ll be fine while he is in school, but they have been using the “National Guard” to fight the wars in Iraq and Afghanistan for the last couple of decades. Since 9/11 the national guard has been used extensively in combat operations abroad. There are also the considerations of obligations after school. He will be required to serve a number of years before being able to get out, which means overseas service while active, and then at a whim Brandon can call them up and send them to Ukraine to fight, or in his case your relative will be fixing the wounded. Then there is the question of whether there is a stop-loss order in effect, which means that you can’t muster out or resign your commission until the stop-loss is rescinded. I had a friend who got caught by this back in the early 2000s and he couldn’t resign his captaincy for 3 years. Even once you resign\retire you are subject to recall for national emergencies. Nat Guard also gets called up for natural disasters, which happen every year in the US - tornadoes, hurricanes, floods, BLM protests, Antifa protests, etc. Keep in mind that the national guard was called up for the Jan 6th farce, and were sleeping in an unenclosed parking deck (during the winter for some of it) for the better part of 6 months.
My personal opinion would be that he would have a shorter term obligation if he joined the Air Force ROTC, then served the 4-6 years of active duty afterwards. The problem with this is that once the bachelors degree is obtained and he is commissioned as a 2nd Lieutenant, he will have to meet that obligation before going to med school. Stop-loss and recall are still part of this, but you won’t be called up suddenly if you are active duty for 4-6 years and then get out.
Regardless of what direction he goes, if he joins he will need to do basic training right away (in whatever window the service requires) So figure 6-12? (marines are 12, aren’t they?) weeks depending on branch.
Lot of decisions and variables to be made.
plus all the woke training he would have to deal with. And keeping his patriotic service oriented mouth shut about anything that is happening. can’t be one of those ultra right wing patriotic samurai-soldiers who loves his country.