India

In Kolkata the list of top 10 college are:-
Jadavpur University
IEM
Heritage
Techno India Salt Lake
St. Thomas
RCCIT
Techno Rajarhat
BPPIMT.

Follow the following link:
https://www.shiksha.com/science/colleges/b-sc-colleges-Maharashtra

You got good rank. Yes, sure you will get seat in CBIT Hyderabad.

With the rank of 26k, no national law university admits a student, unless you are a domicile of Maharashtra (you have chance of getting seat at either of 3 MNLUs). Else, some universities and colleges admits students based on their CLAT score. The list of Universities could be found at http://information.clat.ac.in/pdf/Institutions using CLAT Score. Pdf.

Category rank decides the admission to certain extent only at NLUs, as each NLU has different set of rules for reservation. It is advisable to come back with the All India Rank to predict the admission into universities based on past trends.

Yes, you can. But, for that you need to attend all the 3 counseling rounds, because your rank is a little low, but you can be lucky in any of the counseling.

In home state OBC rank, you compete with the candidates of OBC Category in your state only. And, with all India OBC rank, you can compete with the candidates of OBC Category with in India.