sir how to use EWS certificate for gate exams

The students belonging to the EWS category will have 10% of the total seats alloted to general category students reserved for them. They will benefit as they will be able to compete for both the general category seats as well as the EWS category seats where the competition will be less.
If you come from EWS category, you can stake claim on 40% unreserved seats as well as 10% seats reserved for EWS category. Your cutoff for admission to M.Tech/MS courses in IITs will be lower than general category students.