hello sabyasachi singh roy,

yes you should appear and get qualify through jee mains before jee advanced.it is the only qualification you need for jee advanced.jee advanced is the quaification needed for the ug courses in iit's.

to know more about jee advanced,please refer this link:

https://engineering.careers360.com/exams/jee-advanced

all the best

I Hope this information will be useful to you.

if you need additional information,let us know to help you.

Thank you!!!:)