First of all get your ews certificate and apply for jee advanced under EWS category

In IITs there are nearly 500 seats for EWS category and those are also in old IITs so try to improve your rank in advanced

And for the 40–45k rank (general) you can join NIT for chemical,biotech,and metallurgical engineering

And those branches are also very good

One more thing after joining to NIT for lower branch you can change your branch by scoring well in first year of BTech .so there are very much chances for you to be NITian.

Hope you got the answer you are looking for thank-you.