Hello Poojitha, You mentioned in the question you have secured 69.81 percentile in JEE Main, being an OBC candidate. You are also interested in pursuing B.Tech in CSE from any NIT or IIIT. Based on your percentile, your AIR should lie within the range of 308844 - 347185. Well, as far as previous years' cutoffs are concerned, your performance is not up to the mark and your marks is not enough to be eligible for getting admission at any NITs or IIITs, let alone CSE course.

If you refer to previous years' cutoffs you will see to get into NITs or IIITs, a candidate should try to get at least around 90 percentile to be on the safe side, even if you belong to OBC-NCL. For instance, to get admission for CSE in NIT Surathkal , 2020 Cutoff ranks for OBC-NCL Female were 8583 (Home State ) and 1534  (Other State). For NIT Warangal, the 2020 Cutoff ranks were 54636 (Home State) and 19725 (Other State).

If we now take any one branch of IIIT into consideration, IIIT Gwalior then in 2020, JEE Main Cutoff trend for OBC-NCL Female to get admission for CSE was 3239.

I hope you have got an overall idea about the eligibility criteria for NITs or IIITs. Its difficult for me to give all the cutoffs for all the branches of NITs and IIITs here in this answer. So, check out these two links to get a detailed picture about the cutoff trends: https://engineering.careers360.com/articles/jee-main-cutoff-for-top-nits

https://engineering.careers360.com/articles/jee-main-cutoff-for-top-iiits

If you want to know your eligibility in other colleges based on your rank then check out JEE Main 2021 College Predictor:

I hope this information helps you out. I wish you all the best for your future and career.

Thank you.