Hey there the eligibility criteria for the nits is that you have to score at least 75 percent in your 12 class that is 375 mark minimum you have . If you are not fullfilling the basic criteria so your are not eligible to take admission in any of the nits .

For more information visit this link:->

https://www.google.com/amp/s/engineering.careers360.com/articles/new-eligibility-criteria-for-nits-and-iiits-admission-says-mhrd/amp

Hello, 
The students with a minimum of 75% in their 12th are eligible for applying for seats for nits or iits. Even if you have good score, you won't be able to get a seat, if your 12th grade score is less than 75%. 
Good Luck!