If you’re a Canadian citizen and low income, you are eligible for financial aid from the province. If you’ve lived in Canada, you would apply to the province in which you lived. If you haven’t lived in a province, you would apply to the province where the university is. Here’s Ontario’s website for example https://osap.gov.on.ca/AidEstimator1819Web/enterapp/enter.xhtml
Those full ride scholarships are extremely competitive and are only open to non-Canadians.