Hey Lokesh!

National admission test is conducted by VMC to select students for its two year classroom program who have been recently promoted to class 11th . Based on the scores and performance in this test , admissions are done  for different  programs at multiple centres across India. You need to choose the program suitable for you, then register for the test , get your admit card and then appear for the test to get admission in VMC. 

You can visit their official site for all the information:

www.vidyamandir.com

I hope this helps you!