No College degree required!
When joining the Navy, which some people do right after high school, they give option for jobs. HM is one of those jobs you can do right after high school and make of it a 20 year career. The Navy will ensure your training and schooling for this career.
A School
Basic Clinic Procedure.
After basic training, which everyone has to go through, depending on your job in the Navy you will be going through some schooling for that job. In a HM case, your schooling will consest of learning about learning clinical procedure and or learning about physical treatments.