B.Sc

No, dropping a year after class 12th won't make you ineligible to pursue any course.

If you are planning to take biotechnology as a career option, then you have to be very clear that you have to continue your studies till Ph.D or at least Master's degree because Bachelor's degree holders or Diploma holders will not have any scope as it is more inclined towards research.

Food science is a blooming course in our country. If you can understand it well, then you can reach at the top. If you can pursue M.Sc, then you can go for higher research or you can join as a food nutritionist. But, according to me research is the best option. You can explore more and will receive many opportunities.
Best of luck.

You can become an executive, manager, assistant manager, business development manager, sales manager, chef, etc. in hotel industry including fast food chain, travel agencies like clearTrip, Thomas Cook and 5 star hotels.

National Institute of Design is the best college to pursue B.Sc in interior design.

Yes, you can. Currently, IGNOU, Anna malai University and few other state open universities are offering B.Sc through distance. It is tough to pursue B.Sc from IGNOU as compared to any other conventional university.

It is not possible to pursue B.Com and B.Sc simultaneously. B.Sc is pure science and you must have strong concept of the subjects to pursue it. You can first go for B.Com, then you can invest your time in understanding the science subject, and then you can go for B.Sc.
It means a total of 7 years is required to complete the whole process. But, every college has some eligibility criteria, which you must fulfill to get admission for B.Com or B.Sc.
Best of luck.

Hi,
Yes, you can pursue psychology program in Master's degree after completion of any Bachelor's degree from a recognized university.
A graduate in psychology can seek jobs in various sectors such as private industry, universities, school and colleges, clinics, hospitals and in government agencies. Some graduates work under the management of Doctoral level psychologists.
Psychology students can also work in health centres, as assistant in administrative department and rehabilitation sector. A student in international relations gets more preference in physiology field.
All the best.

If your 1st year admissions is through any legal authority, then contact them to change the university. If they have such rights, they should help you.