Hello Vasu,
JEE has released a set of cutoffs for various categories for qualifying to JEE advanced from JEE mains. The cutoff for OBC category is fixed at: 74.3 percentile. Anyone clearing this fixed threshold and belonging to OBC category is eligible for JEE advanced. Given that your percentile is 76.7, you are eligible for JEE advanced.
To find out the colleges you can get with your JEE mains score visit the following link:
https://engineering.careers360.com/jee-main-college-predictor
All the best.
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