How can I be a better engineer if I am not in IITs or NITs?
Simply being in IIT does not make one a good engineer and similarly, not being in IIT is not a hinderance in being one. Specially now, when all the lectures are available via NPTEL channel (and other MOOCs like Coursera, Udacity etc).
You need to have the drive, the drive to always keep learning and updating your skills. If you have that, you don't even need a degree to be an awesome engineer. You will automatically become one.
IITK, Management Consultant