After 12th you can apply for NDA to join Indian Army. Here are the eligibility criteria:
The candidate should complete the 12th standard from any recognized state board of india.
There is no minimum percentage required to eligible.
The science stream candidates are eligible for the indian air force and navy.
the applicant age limit should be between 16.5 to 19 years.
There is no age criteria for other categories.
The applicant should be citizen of india.
Only unmarried male candidates are eligible for this exam.
Girls are not eligible for this exam.
The candidate should be physically and medically fit for this exam.
for more details visit the website
all the best.