The National Institute of Engineering Cut-off

I am not getting why you want to join NIE Mysore. Better you prepare for NIMCET for few months and clear the competitive exam. Based on your score, you will get prestigious institutes like NIT Trichy, NIT Surathkal, NIT Allahabad, etc.
Otherwise below is the detailed information:
50% Candidate must have passed any recognized BCA / Bachelor degree in Computer Science Engineering or equivalent degree and obtained an aggregate minimum of 50% marks (45% of marks in case of SC, ST and Category-I of Karnataka candidates) taken together in all the subjects in all the years of the Degree Examination from any recognized institute/university. OR Candidate must have passed B.Sc. / B.Com / B.A. with Mathematics at 10 + 2 level or at Graduation level (with additional bridge courses as per the norms of the concerned University) and obtained an aggregate minimum of 50% marks (45% of marks in case of SC, ST and Category-I of Karnataka candidates) taken together in all the subjects in all the years of the Degree Examination from any recognized institute/university. Final year students can also apply on provisional basis