Can Canada work as a doctor?

According to the Canadian immigration law, if you get a full-time job invitation from your work unit, you can apply for a work visa in Canada, but you can only get a work visa first, not a green card. You must work full-time in Canada for two years before you can apply for a Canadian green card. But if it is full-time, it is in conflict with getting a student visa to study for a doctorate. Note that part-time jobs are allowed during the doctoral period, not full-time, but part-time. Of course, Canada allows doctoral students to work part-time, but not full-time. Only when they work full-time can they get a work visa. After working for two years, they can apply for a green card.