Hello!

Yes, you can apply for NDA exam. As per the upsc guidelines led for nda exam 2020, the candidate must be an unmarried man, falling between the age group of 16.5 to 19.5 years. For army he should have cleared 12th class and for navy/air force he should have cleared 12th clas with maths and physics. So, you fall in the eligibility criteria.

You can apply.

For more information: https://www.google.com/amp/s/competition.careers360.com/articles/nda-eligibility-criteria/amp

I hope this helps.