hi,

ews stands for economically weaker section, students who does not belongs to any other category, have satisfied the criteria given for ews category are eligible to apply for it. now coming to nits, admission to engineering courses is based on jee main exam, 10% seats are reserve for ews category in nits or institute under central government.

Admission to IITS is based on jee advance score, you need to first qualify in jee main exam, then you would be eligible for jee advance test. however 10% seats are reserve for ews candidates for admission to b.tech courses.