Hello,I need some guidance. I have completed my graduation in computer science from India. I want to study management courses in Canada or Germany. Should I go for management course or stay in my field. Please suggest me.

This depends on your goals. 

If you are looking to transition into one of these countries and work there, you need to consider a number of factors.

Of primary concern is the local language. Duncan has an excellent post on this here:

https://find-mba.com/board/europe/do-you-need-to-speak-the-local-language-29546

The short story is that unless you already speak the local language in the country where you anticipate studying, it will be hard to get a management-level job. The situation is a bit better for those looking at non-MBA level, more technical positions, but if you don't speak the language, you will still be at many disadvantages, which will reflect in salary, among other factors.

Germany is a great place to study, but if your goal includes working in the country after graduation, you might want to consider learning the language to a fluent level before studying there.

Canada tends to be a better option for most English-speaking international students. Of course, the best opportunities come from the highest-ranked schools, which will of course require excellent applications, and a very strong, and balanced, GMAT score. Note that without work experience, you will be looking at master's programs like master's in managements, and NOT MBAs.