NDA

Unfortunately, you can not join as a Commissioned Officer in IAF after 10+2 without appearing for NDA. You can join IAF after graduation degree. Any graduate or engineer can join Flying branch in Indian Air Force subject to meeting other criterion. The following are the three modes of entry for Graduates/ Engineers to join the Flying branch:
(a) Combined Defence Services Examination (for men only): CDS examination is conducted by UPSC twice a year. Eligibility criteria to appear for CDS is age between 20 to 24 years single males and three year degree graduate in any discipline from a recognised University (with Physics and Mathematics at 10+2 level) / BE /B.Tech (4-year course). Advertisements are released by UPSC in the months of June and November.(b) NCC Special Entry: As an Air Wing Senior Division C Certificate holder of the National Cadet Corps, cadets can apply to the Flying Branch of the Indian Air Force. Men can join the Air Force through this mode of entry and will be given a Permanent Commission. Remaining eligibility criteria are same as CDS entry. NCC Cadets are to apply through respective NCC Air Squadrons/DG NCC.
(c) SSC (Short Service Commission ) entry( for men and women). Graduates both men and women who are single can apply through AFCAT for Short Service Commission (SSC) in the Flying Branch. Short Service Commission in Flying branch is for 14 years with no further extension. Remaining eligibility criteria are same as CDS. Upper age limit for Candidates holding valid and current Commercial Pilot Licence issued by DGCA (India) is relaxed up to 26 years. Advertisements for AFCAT are released by the IAF in the months of June and December.
In addition to the flying branch, you can join other ground duty branches. You may refer to following link http://careerairforce.nic.in/ for further details.

Educational eligibility criteria for appearing in NDA examinations is as follows:
(a) Army Wing of National Defence Academy: Candidates applying for Indian Army must have passed class 12/HSC in 10+2 pattern of school education or equivalent examination conducted by a State Education Board or a University
(b) Air Force, Navy and Naval Academy of National Defence Academy: Candidates applying for Air Force, Navy and Naval Academy must have passed class 12/HSC in 10+2 pattern of School Education with physics and mathematics conducted by a state education board or a university.
There is no minimum percentage mentioned in the eligibility criteria.