how many marks are required In jee main to get into a top IIIT in CSE . I belongs to OBC-NCL category .

Hello Lokesh,

To get seat in IIITs you have to get Rank below 8000 in JEE examination to get top IIITs. Also cut-offs varies from College to College and year to year. You must get above 170+ marks to get good Rank and seat in good IIIT.
Cutoffs for Some Top IIITs are given below.
IIIT Surat
Computer Science Engineering
Opening Rank - 6094
Closing Rank - 10042

IIIT Kanchipuram
Computer Science Engineering
Opening Rank - 5020
Closing Rank - 6794

IIIT Pune
Computer Science Engineering
Opening Rank - 4884
Closing Rank- 8936

IIIT Ranchi
Computer Science Engineering
Opening Rank - 8340
Closing Rank - 12876

IIIT Kottayam
Computer Science Engineering
Opening Rank - 8957
Closing Rank - 14151

To predict JEE Mains Rank using your JEE Mains Paper-1 Percentile use below mentioned link.
https://engineering.careers360.com/jee-main-rank-predictor

For information about JEE Mains 2021 expected cut-offs go through below link
https://engineering.careers360.com/articles/jee-main-cutoff

To get more information about opening and closing ranks in IITs, IIITs, NITs, IIESTs and NFTs are given below.
https://josaa.nic.in/Result/Result/currentorcr.aspx

You can predict Colleges for your JEE Mains Paper-1 Rank using given below link.
https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

Thank you!!