Hii Rohit,

One can join Indian army, after 10th or 12th or after Graduation technical or non technical basis.

after 10th, if you have NSS certificate ( optional), you can join army as a soldier. Then with training and internal exams can move to the higher rank.

 You can join army as an officer rank after your Graduation with minimum 50%.

Also you can join  IMA, if you clear your NDA exam and SSB interview but for For the NDA entry, one must have 10+2 schooling.

Hope this helped!

Good luck!