Canada

I know of Masters in International Business or Global Business offered by top universities like Queen's University, University of Victoria and Master of Global Affairs by University of Toronto.

Hello Harshal,
I believe you must choose this yourself. You will know better what you want. Pursue MS in civil engineering disciplines if you want to stay in this field. If you feel the need to switch to another career path, do accordingly. Your options include management, urban planning, landscape architecture, interior design etc.

Which course are you applying for and what is your qualification?

Kindly specify the field in which you want to pursue PG Diploma.

Fanshawe is a very popular college among Indian students as it comes under the SPP. The college has good brand value and the presence of strong Indian student community will make it easier for you to settle down.
As far as the scope of any course is concerned, you need to remember, getting a job depends on you and your caliber. If you score really high, then it is possible to get a well-paying job. Also, getting a job abroad doesn't depend 100% on your scores, your networking skills matter a lot. So the more active you are, the better are your chances.

It depends on why you need to pursue it. If you are saying 'better' then please mention what you wish to compare it with.

You can pursue post graduate diploma in the same specialization.

Do you wish to pursue a course in Canada or you wish to get a job with your Indian diploma?

University of Toronto, University of Alberta, University of Waterloo, McGill University could be the best options. Visit the university websites for admission requirements. These are competitive universities.