Editing

This is totally at the discretion of the college officials. I Would request you to contact college officials for the same.

Hi Meghna,
There is a placement cell in St. Xavier's College, Kolkata. If you register there, you can opt for placement facility.
Students of this course can register there.
So yes, you can have placement. I would suggest you to look at previous answers of questions related to placements and also visit the placement cell page on the website and Facebook.
All the best.

As the fees is not disclosed by the college officials, I would request you to contact them directly. The course offered is part-time.

Yes, you are eligible to apply for Certification in Broadcast Editing.

FCP - Final Cut Pro is taught to students who do their graduation or even post-graduation in Film Making, Media Production, Editing, Visual Editing, etc. If you are not opting for a Formal Degree after 12th then you have to find out some academy at your possible preference of place. Private academies shall share what their fee is same for computer hardware.

Many courses are available according to the interest of the people. So, Google it.