Dear Aspirant, you can check previous Year cutoffs (closing ranks) for NIT Delhi at official JOSAA website :

https://josaa.nic.in/Result/Result/currentorcr.aspx

According to previous year cutoffs 99.1 + percentile would help secure a CSE seat at NIT Delhi

You can check all your options using these tools:

JEE MAINS RANK PREDICTOR-

JEE MAINS college predictor :

https://engineering.careers360.com/jee-main-college-predictor?ici=cp-listing_engineering&icn=JEE-Main-College-Predictor

JEE Mains 2021  Rank vs Percentile vs Marks :

https://engineering.careers360.com/articles/jee-main-marks-vs-percentile

Also these might help:

JEE Mains preparation tips:

https://engineering.careers360.com/articles/jee-main-preparation-tips

https://learn.careers360.com/knockoutfull-jee-main-april/

Hope this helps.