Hello aspirant.

i believe you want to join Indian armed forces through NDA.

coming to the question, NDA is an exam which has the syllabus of only high school. and the age to join is between 16.5 and 19.5 (at the time of joining). And also you need only a 12th pass to appear for this exam. Though you can attend college during application, it is not considered significantly.

NCC is not essential to join NDA. NCC entry is a completely different entry. So, if you finish college, you will cross the age eligibility for NDA and you will have only CDS, AFCAT, NCC entry, TGC as your mode of entry. So, you need to choose college only for these entries.

NDA itself is a college. Also it is the best college in India. So, prepare well and attend the exam immediately after 12th and clear SSB, then join NDA. So, you can join any college and try for NDA till you meet the eligibility criteria (age).

If you will join only after college then NDA is not your option. Try other modes of entry.

I hope I answered your question.

good luck.

Feel free to ask any doubts in the comments.