Dear leaner,

Your concern for the best friend is so kind of you, as he completed his higher study it is the best ,one of the option to join in defence.

Infact defence needs a good in academic too but with atleast passed in 10th

Eligibility is one must have 12th with 50% all over ,and mandatory to have physics, chemistry, maths, English at 12th and must score 40% in all subjects.

Better the age must be 16.5- 19 years between. And mainly choose one with physical standard test,tell him to practise and look over these things more .

All the best.