In fact, there is no requirement to be employed at all during the course of your studies, though the vast majority of candidates do tend to be working full time. Of those employed, roughly 50 per cent work at accounting firms and roughly 50 per cent work in industry, the public sector, and not-for-profits.
However, you will need to gain 30 months relevant practical experience with an employer (in any sector) within seven years of starting the CPA Professional Education Program (CPA PEP). The key is to gain relevant, paid employment that is progressively challenging so as to develop as a professional accountant with appropriate supervision and mentorship.
Read more about the CPA Practical Experience Requirements