JEE

I would recommend you University of Engineering & Management (UEM) under IEM group. Government of India, MHRD, NIRF has ranked IEM group as 3rd in Bengal after IIT Kharagpur and NIT Durgapur. The top 4 of Bengal within 100 in order are:-
1) IIT Kharagpur
2) NIT Durgapur
3) IEM Kolkata
4) IIEST Shibpur (Formerly BESU).

Yes, you have definite scope to get into top NITs.

Am giving you the book name which may help you.
1. R. S. Agarwal [Arithmetic]
2. Dr. Lal and Jain
3. N. C. E. R. T. Math Book [standard. Ix to standard. XII]
Thanks.

If you can give LPU NEST please try to get in touch with LPU admissions cell, there might be a chance.

The seats which are allotted under the convener quota I. e, based on your EAMCET rank and the reservation is an A category seat. Every private college (almost all) gives some extra seats irrespective of your reservation status (OC, BS, SC, ST) based on the JEE Mains score. These seats are said to be B category. Students opting these seats must withdraw their convenor quota seat. Students need to apply separately for their desired colleges with a nominal fee of 2 to 3k. The college fee under this quota is same as the seat acquired under convenor quota.

The ranking system changes every year.

Based on the JEE Main OBC rank you obtained, You can get the following options.
1. IIIT Allahabad (IT)
2. NIT Trichy (Mechanical)
3. NIT Surathkal (EEE)
4. NIT Calicut (ECE)
5. NIT Warangal (EEE)
6. SVNIT Surat (CSE)
7. MANIT Bhopal (CSE). .