B.Sc

Hello, yes you are eligible for M.Sc in physics.

College name matters a lot and so does the market value of the college.
Doing B.Tech from IIT and B.Tech from some ABC college are different, so is the case of B.Sc in nursing.

Hello there,
Physics and chemistry are the compulsory subjects in HSC. In the elective courses, you can either choose maths or biology.
Regards.

In B.Sc You learn everything in general but you don't get any specialisation like botany, zoology, physics, chemistry or maths. You become simple Science graduate. But the third year or B.Sc. Honors give you a specialisation like botany zoology and physics etc. Till 2 years you study general course of Science along with subject you entered on third year you specialisation on specific subject. It is advisable to do BSc hons because it gives you a much better scope for further studies.

Yes, why not. In fact, you must have had economics in you 12th. So it will be good for you. If you are okay with the subject and find interest in it, then go for B.Sc in Economics.

I have heard in Punjab, there is Lovely Professional University link is http://www.lpu.in/programmes/bsc-hons-zoology. They provide the proper placement options and professional grooming.

Practically speaking, all the courses that you have mentioned are the same. It is just the change in nomenclature. AICTE approved colleges provide 4 years degree whereas all other institutes (including NCHMCT) offer 3 years degree. The content of the syllabus is more or less the same. Instead of the course or name of the course, you should look at the placement of the institute/college that you choose.