Hello Tripathy, 

Yes you will be eligible for admission in acms under defense quota if your father served in the army or other branches of the army such as navy, air Force,  etc. Army quota is for the wards of those personnel who served in the army itself. 

Another eligibility criteria is that the applicant must have 50% marks in his PCB and English in his/her 10+2 exams.  

Hope this helps :)