hi,

see it seems you are having a great difficulty to understanding the NDA exam and the courses which would be taught. NDA is one of the most sought exam in India. The exam is conducted for admission to Army, Navy and Air Force wings of NDA and Indian Naval Academy Course (INAC). it conduct two times a years which follows by written test and ssb Interview. after that there would be three years training and degree would be awarded which is affiliated by jawharlal nehru university.

On successful completion of the three-year course, Army cadets proceed to Indian Military Academy at Dehradun, Naval cadets to Indian Naval Academy and Air Force cadets to the Air Force Academy . After completion of one year of training at their respective academies, they are commissioned as Officers into respective services.

so after COMPLETING THE one year training you may appear for IAS exam. for indian civil service exam the eligibility criteria is  candidates must hold a bachelors degree in any discipline.

hope it  would help.