Bachelors

It totally depends upon your field of interest and specialization.

Yes, why not.
If you are interested and have scored satisfactory marks for fashion designing, then you can proceed for Diploma.

Different colleges need a different cut off. This varies year to year. You can see all the details on the official website of each college. Backlog is not that much of problem once you clear it. It may even go unnoticed. Always keep your answers ready for the interview, just in case.
Top colleges: 97+
Good college: 94-95+ usually
Decent colleges: 85+Depends on the criteria set for each year.

No, it should be at least 3 years, and it is basically considered as illegal by Govt. of India.

Yes, there are many good colleges in North India:
1. Delhi Technical University
2. Jaypee University
3. Amity University
4. NSIT Delhi
5. YMCA University
6. Galgotia's University
7. DIT University

Hi Ritu,
Please find the list here https://www.shiksha.com/mass-communication-media/articles/top-10-mass-communication-colleges-in-india-blogId-13552

1. DNYS (Dipoloma in naturopathy and yogic sciences) is the first program available to anyone with +II education.
2. BNYS (Bachelors) is a multi-year program offered by a limited number of Universities.
3. So far no Indian University seems to have gone beyond BNYS.

It is not possible. As school life is from class nursery to class 12th, in the same way UG courses are either of 3/5.5/4/5 years, depending upon the course. You have to clear all the year semester exams in order to graduate, and you need to graduate as soon as possible. After that work hard and clear all the semester exams in one attempt in the allotted years of various courses.