Hello Satyam,

You are from Commerce with Maths stream so you can opt for B.Com(Hons) course. See, admission process and eligiiblity criteria vary from college to college. Many colleges offer admission to Undergraduate courses on the basis of marks in the qualifying exam (Class 12th).
Like, Delhi University offer admission to most of the UG courses on the basis of merit.
And, GGSIPU conducts entrance test for admission to UG courses.
Do let me know If you wish to know about any other college/University or if you have any other query. And , as you have mentioned that you are preparing for NDA exam also, so do you want to know anything about the NDA exam also?

Good Luck!