I would suggest you to give NIMCET exam as this is a naional level test for NITs so this would be best option. Apart from it, there are other options also like IIT-JAM, BIT MCA, IPUCET MCA, JNU MCA, Pune University MCA, West Bengal- JOINT ENTRANCE EXAM MCA (WB-JECA) and at college level there will be many choices so kindly be specific in which university/college/exam you are interested so that I can help you with the further procedure.

Good Luck!!!