For MNNIT or Motilal Nehru National Institute of Technology, Prayagraj, you need to score well in the JEE Mains. You should atleast score a 75%+ in the plus 2 examination and your rank in your state must be in top 20 percentile.

A safe score would be 85%+ in the plus 2 examination and a top 15 percentile in your state.

All the best