My GATE score is 496 , SC category, my AIR is 4342 , If I say I m only concerned with placements with package above 7lpa ..but placememt is must , so should I choose top3 NIT or new IITs? and since I have to even workon my coding so should I opt for data science or general CSE?

Hi,

These are the choices which match your score and there is good probability that you will get a call from them.
IIT Bombay-Computer Engineering(Geoinformatics and Natural Resources Engineering)
NIT Uttarakhand-Computer Engineering(Artificial Intelligence)
Central University of Rajasthan-Computer Engineering(Information Security)
NIT Srinagar-Computer Engineering(Communication & Information Technology)
IIIT Vadodara-Computer Engineering(Computer Science & Engineering)
IIIT Srirangam, Trichy-Computer Engineering(Database Systems)

Form placement perspective you should choose old IITs primarily after them you can go for NITs