If you join Afmc as undergraduate u have to sign a bond of 25lacs to serve in Indian armed forces for at least 7 yrs. Once u complete MBBS, you will get an option to join as short service officer /permanent service officer. You can break the bond and pay out the entire bond amount. If u select short service, you have to serve 7 yrs in the Armed Forces .Then u will be released from the bond. Now coming to your posting, a doctor is where his or her need is. You will be ideally placed in the hospitals and clinics of Aurforce, Army and Navy.