Hello Mukul

You have to secure atleast 85 percentile marks ( may be more depending upon exact statistics).

But it is not all about qualifying ; jee advanced is a good level exam and if you are prepared for it than you must do good in jee mains also.

And in jee mains you have to secure a good rank for good NIT / College. And to secure that much percentile you have to score minimum 90-100 + marks ( may vary ).

So good luck