Anything is possible but without sharing your qualification profile nobody can really comment although as in many countries getting into medical school is likely fiercely competitive and for international students expensive. On a study permit you can only work 20 hours a week so do not bank on that covering much more than some basic living expense . Should really post in the international student section.
Optometrist isn't a doctor and there is a separate degree program for optometry. Both medicine and optometry degrees are extremely competitive and the courses are very expensive. The courses are too demanding to work part-time.
Yes you should share your details so that I can tell you proper guidance. If you are looking for job in canada then you should visit http://www.workanada.ca/, the ultimate job search engine for canada.
Optometrist isn't a doctor and there is a separate degree program for optometry. Both medicine and optometry degrees are extremely competitive and the courses are very expensive. The courses are too demanding to work part-time.