If you want to get admission into Computer Science and Engineering in National Institute of Technology Silchar in the Schedule Tribe quota, then the cut-offs for the same for 2021 are as follows:

Opening Rank (6th round): 711
Closing Rank (6th round): 977

So, you'll have to get a rank in the range of 700 to 1,000 to get the same under the required quota. All the best!