Modelling

You may pursue modelling from any of the institutes mentioned below:
https://goo.gl/itTY84
It is not the institute that matters while getting the opportunity/break, it will be your skills that will matter.

You can either pursue modelling course for acting course after completing 12th. Refer to the link below:
https://goo.gl/1ZSt7n

I would suggest you go for a short term course first and then decide whether it interests you or not. The best thing would be not leaving engineering in a jiffy as changing careers can sometimes lead to a bad choice.

There is only one way to go about it and that is you take admission in a graduate degree for filmmaking. You may try for FTII, Pune as that is the best institute in India if you actually wish to make a career in the same.

No, if you wish to become a model, then it would be better if you pursue a modelling course instead of pursuing fashion designing.

Dear,
According to me you should focus on your Physical fitness and Join professional degree in graduation. During your college period try to involve in college events and try outside for small project which give you base .You can think of professional portfolio and then send to leading Model coordinator in Delhi or Mumbai for the opportunities.
All the best.

Kindly refer to the link below:
https://ask.shiksha.com/i-want-to-become-a-actor-and-model-what-should-i-do-after-12th-and-side-by-side-can-i-complete-my-graduation-qna-2674483

You can either go for a diploma or certificate courses in modelling. Refer top the link below:
https://goo.gl/Pm4Xux

Kindly click on the link below to check the colleges:
https://goo.gl/3hXTXo