hi,
I assume you are asking for jee main exam, see you need to apply from ews category, and complete the undertaking form , students may submit their original from upto the end of may, in case you have applied from general category, you can not submit the ews certificate since you will not considered for ews category.
To know about complete list of probable college name, based on your score, category please use Careers360 college predictor tool,
https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer
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