What is the minimum SC percentile to get a call from IIT-Delhi having Non-engineer (Background)?

cut offs for reserved sections can be very low, RTI data suggest CAT percentile as low as 50% was offered admission last year so it is always better to apply.

Hi team, How to apply for Sp jain and IIT's? Do we have to apply through their websites or will we get calls based on our CAT score?

The SP Jain application deadline was November 25, and IITs may still be accepting applications. You can check out their websites separately

CAn you please suggest me which will be better mba marketing or mba finance as i am a fresher with no background in finance or maths

Generally it's better to go for Marketing/HR. In Finance, I have heard from seniors that in top IIM's, FMS, XLRI etc, during placements, for finance roles, companies generally prefer people with CA/CFA background over others.