Colleges in Varanasi

Yes, Absolutely, A Graduate in any science stream (Chemistry, zoology etc.) can apply for M.Sc in Food Technology.
M.Sc in Food Technology is a 2-year postgraduate course. Food Technology is the branch of food science involving the processing, protection, preparation, selection, distribution, and utilization of sheltered, nutritious, and healthy nourishment.

Yes, with these marks, you can get admission. You can apply for admission here.
Good luck.

I would suggest you to continue with your B.Tech as B.Tech degree has more value than B.Sc(Hons.)

Yes, with your category you will easily get a seat here.

There are end number of opportunities after doing Master's in zoology. You can go for research, or do Ph.D. then lectureship or start working for animal rights as you can join some organisation. All the best.

Cutoff is General: 1319, 173, OBC: 707,165, SC: 481, 187, ST: 273, 53.

Yes, you can get admission in PG Diploma or MA course according to your interest. you are eligible for both.
Good luck.

You can know their admission processes by visiting following link
https://www.shiksha.com/university/bhu-banaras-hindu-university-Varanasi-23336/admission
For GGSIPU
https://www.shiksha.com/university/ggsipu-guru-gobind-singh-indraprastha-university-Delhi-24725/admission.