It'll depend on how recent it was usually, but a misdemeanor marijuana charge probably won't keep you out of the Guard. I've known people who've gone active duty and have gotten security clearances with a weed charge on their record.
The person who can give you a definitive answer, is the National Guard recruiter.
No.
no
No, you cannot.
A loan default wouldn't disqualify you from joining the National Guard.
Not FOR joining the National Guard or Guard obligations, but that does not mean they can't fire you for other reasons.
Depends on the specifics of your crime. You need to speak to a National Guard recruiter for a definitive answer on this.
Yes
Yes.
First, there is no Air Force National Guard. It is called the Air National Guard. The military does not train anyone to become a doctor. You would go to med. school yourself and upon completion of the course, join the Air Guard as a physician.
Depends on the type and for what condition.
It is usually not a bad idea.
yes