It depends on what you mean. A “regular” doctor/surgeon and an army doctor/surgeon are trained the same. The difference is that that army one is in the military and is an officer upon completion of medical school. They all went to college, med school, residency, and +/- fellowship. The difference is where they did residency and fellowship. There are civilian programs and specific military programs (San Diego, San Antonio, Walter Reed, etc).
If you mean a medic and not a doctor/surgeon, they get additional training after boot camp with the goal of being able to stabilize the wounded on the battlefield to take them back to the doctor or surgeon on the local base. The doctor/surgeon on the local base will then generally perform further stabilization to transfer the patient to a designated military hospital (e.g. Germany).
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