Hey!

The Eductional qualifications for giving the NDA exam are:

•For the Army wing of NDA:Candidate should have passed 12th or equivalent examination from a recognized board

•For the Air Force and Naval wings of NDA and 10+2 Cadet entry scheme at INA:Candidate should have passed 12th or equivalent examination with Physics and Mathematics

• who are appearing in 12th or equivalent examination can also apply for the exam.

So, you can give National Defence Academy (NDA) exam according to the above eligibility criterias and you don't have to give any other exam before giving NDA exam.

For further details you can visit this provided link : https://www.google.co.in/amp/s/competition.careers360.com/articles/nda/amp?espv=1

Hope this helps.