West Bengal doesn't have Institutional quota which means though you have studied your 10th and 12th from West Bengal, you cannot claim their domicile. To be eligible for West Bengal domicile, either you should have been residing in West Bengal for atleast 10 years or either of your parents should have been permanent residents of West Bengal and have a permanent Residence in West Bengal. But if you have studied your 10th and 12th in West Bengal, you do not qualify for being considered as the domicile Candidate of the State.

Hii Vibhu!
This depends on whether you have the bonafied certificate or the domicile of West Bengal or not. It also depends on the state policy. Some states allow the bonafied students to get reservation whereas some states require both domicile as well as bonafied to provide reservation. You must get this information on the official website of the panchayat or taluka wherein you can download the hard copy of domicile, fill it and submit. Your school authorities may also know about this. So, you can enquire from them as well. Hope this helps.
Good luck!