Hello Hemendra,

Definately, you should mentally fit for join Indian military academy(ima). Body must have maintain both mental fit and physical fit .

To mentallay fit follow some rules .

1. Do Yoga and Exercises  daily it will improve the concentration and focus.
2. Eat proper food and follow balance diet.
3. Do more different problems like puzzle, brain twister e.t.c.
4. Don't be afraid.
5. Maintain good sleep.
6. Maintain good health.
7. Don't take stress and pressures.

So,Hemendra this answer will you .

All the best!!!