If we go through the analysis of marks Vs Percentile Vs rank for JEE-Main 2020 then according to the percentile mentioned by you in the question your EWS rank is expected to be in the range of  35000-36000, you can check out marks Vs CRL ranks Vs Percentile from the link given below :-

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

Or

You can also use JEE-Main Rank Predictor to predict your rank :-

JEE Main Rank Predictor 2021 - Predict your JEE Main ...

JEE Main Rank Predictor - Know your expected IIT JEE Main 2021 Rank by ...

JEE Advanced 2021 Eligibility Criteria has been revised . Candidates must check the complete eligibility before filling the application form. JEE Advance is a national level entrance test organized by IITs under the supervision of the Joint Admission Board. Last year, it was organized by IIT, Kharagpur. This exam is conducted for providing admission to students in UG, PG and other courses in engineering, architecture, science or pharmaceutical offered by IITs and ISM. Students are suggested to check the eligibility criteria before applying. .