hii aspirants 

Let me clear your doubt. 

Here is the eligibility criteria for nda  2019, according to this only unmarried male candidatewhose age is  between 16.5 and 19.5 yearsand have passed or appearing in class 12 (10+2) examination can give the test.for nda 1 a candidate  must be born between July 2, 2001 and July 1, 2004.

And for NDA II, he must be born between 2nd January 2002 and 1st January 2005.

I hope my answer Will help you out

Good luck