Jalpaiguri

First of all, you need to have a domicile certificate of West Bengal. For that either of your parents must be a citizen of West Bengal or you must be a citizen of West Bengal living for more than 10 years or either of your parents should work here. For admission in Jalpaiguri government Engineering College, your WBJEE ranking will be considered, with your ranking you have a chance to get CSE so fill up accordingly. Moreover, even if you get ECE, get admitted and change your stream during decentralized for mop up counselling.

KGEC has better placements than JGEC as per previous records.

Yes, that SC category rank will get you an NLU.

As I don't know what stream you are talking about, I'll give you all the information. Stream - approximately. Cut off GMR
ECE- 200
CSE- 600
IT- 2000
ME- 200
EE -200-250
CE- 150-200.

I hope you asked this question in context to Decentralized counselling. I can't tell about other government engineering colleges but I can give information about Jalpaiguri government engineering college. Approximately 10-12seats remain vacant in each and every stream, and sometimes as high as 16 seats may remain vacant. As usual CSE gets filled first so only higher ranker will get chance, more over many change their streams to CSE in JGEC.

B.Pharma was either never taught or closed many years ago in Jalpaiguri Government Engineering College. And, in case of Jadavpur University, B.Pharma still exist till 2018. If it closes then it'll surely come in news or people will get notified next year while new session admission.

Other state students are required to submit domicile certificate of West Bengal, as the format given in WBJEE site, i.e, either proforma A or B. They can get it certified only if they are residing in WB for more than 10 years or their parent (s) are residents of West Bengal.

Except Jadavpur University, each and every government engineering college considers a West Bengal domicile as a must.
Even though you have a Bihar domicile certificate, you can get a WB domicile, but in some cases. Visit the WBJEE site, you'll find some formats. Those are for domicile certificate required to be shown in Reporting Centres after counselling. You can get the certificate only if you are residing in West Bengal for more than 10 years or if your parent (s) are resident of Bengal.

I think it will be difficult for you to get admission in our college (Jalpaiguri Government Engineering College) with this rank. I'm not even sure about you getting any government college.