If you want to get a student visa in the US, you have to deal with US immigration. You have to apply for university, be accepted, show that you have money to support yourself while you are there. If you have a student visa that is valid for a year or more, you can apply to Canada immigration from the US. You could also apply for a student visa in Canada. I don't know how it works in the US but in Canada if you are on a student visa, your wife can get an open work permit.