It's relatively easy to become a PR if you study in Canada, then get a job (you get a work permit after you study, assuming you study in a "Designated Learning Institution"), and then work for a year.
Financial proof - depends. If you are simply renewing a study permit for the same course (say for example your passport was expiring so they gave you a short study permit), then no, since you have already shown you can pay for it. If it's a brand new course (you finish your bachelors and want to do a masters), then you may have to.