Design

Colleges like National Institute of Design, MIT-Pune are best known for designing. Check the below link too-
https://www.shiksha.com/design/communication-design/colleges/ui-ux-colleges-india.

Yes, you will get a certificate after the completion of your B.Des.

Hi Parul. If you have completed your Bachelor's and Master's then may be, you're looking for the short-term courses in fashion designing. In short term courses like Diploma in fashion designing. Fashion designing has become highly competitive today. If you want to pursue a career in this industry, you will have to work harder and develop several other skills.

Hi Parul. You can find the most suitable college of your own choice. You just need to click the link : https://www.shiksha.com/design/fashion-design/ranking/top-fashion-design-colleges-in-india/94-2-0-0-0
It contains college's placement, fees, exam etc. All the information about the courses or degree is available in the link which I've mentioned above.

Hello Parul,
Fashion designing is a good field for those who were keen interested and dedicating towards itself. If you are planning to work in Top textile Mnc's like Raymond, Siyram, Motto or want to be entrepreneur, definitely fashion designing is a best choice. It is totally depended upon your creativity and skill set. As you are already M.Com graduate, it will be a cherry on the cake. National Institute of Fashion Technology Delhi is top college. All the Best for your future.

Yes,
You can pursue any course after getting Diploma in any course.

It will be tough, but I will suggest you to complete a course first, which you like the most. Then, you can go for other courses of your interest.

Yes, you can get direct admission in fashion Design College in Delhi and institute like:
IIFT North Delhi Campus - Fashion Designing
Fashion Designing Institute Delhi
JD Institute of Fashion Technology Dwarka
Fashionista School
VIDM Institute of Design and Management.