Well, depending on if they were enlisted or an officer, all go through some kind of basic training (army and air force) or boot camp (navy and marines). Obviously the army and marines receive much more intense combat training than the other 2, but all are trained in rifles at a minimum, officers and some specialties receive pistol training or other types of weapons familiarity training. For example, in basic I received INTENSE training with an M16, antipersonel mines, and LAWs (mini bazooka) but didn't receive any training pistols till later on. But that was 35 years ago, so it might have changed and I have No idea what weapon training navy medics receive. And thank you for your kind words.
As far as vehicle training, that is often taught on the job unless its you're particular MOS. Most are no different than a standard car or truck; in fact, most ARE just upgraded civilian vehicles.
Dark Champions source book has a very good background skill package group if you can get your hands on a copy. The skills apply to both 5th and 6th edition with no issue.