WBJEE

I think you will easily get Jalpaiguri Government Engineering College. I got admission for ECE in JGEC with a GMR of 3366 in the year 2017. (I didn't participate in the decentralised counselling).
In fact, you may get IT in Kalyani Government Engineering. College (last year it closed at around 4K). In decentralised counselling, you will get into KGEC for sure.
Still, I will suggest you to study some previous years data before deciding anything

https://www.shiksha.com/b-tech/resources/wbjee-college-predictor
Kindly visit the above-mentioned link.

Haldia Institute of Technology
Heritage Institute of Technology
Kalyani Government Engineering
Academy of Technology, Adisaptagram, Hoogly
University Institute of Technology, Burdwan
Narula Institute of Technology, Kolkata
All the best!

There is low chances. Previous analysis the biotechnology branches cutoff ranking after 3rd round is 20871. So, there might be chances for this year.

Actually, we don't know the marks. We know the rank. Last year closing rank in heritage for CSE after 3rd round is 5030. According to JEE Mains, closing rank till 3rd round is 37364.

From the analysis of previous counselling process, if you wait till the 3rd round, you might get civil in Heritage with this rank.
You will get Applied Electronics in Heritage College with this rank.
In IEM, there is no scope for any branches.

No, you will not get Heritage, try for other colleges.

No, this rank is not suitable for taking admission in Heritage.

In Heritage, you will not get any branches with this rank.

No, you will not get mechanical. I think you will not get any branches in Heritage with this rank.