Generally, no. Foreign nationals who entered Canada with a visitor visa are generally not permitted to work in Canada. To work in Canada, foreign nationals are generally required to obtain a work permit authorizing their period of work in Canada.
Having said this, there are some exceptions in which a foreign national is permitted to work in Canada without a work permit, including but not limited to, foreign athletes or coaches, diplomats, news reporters, religious leaders, and short-term high-skilled workers.
If you are interested in commencing work in Canada and are unsure whether you need to obtain a work permit, please contact Toronto employment and immigration lawyers, Sultan Lawyers, at (416) 214-5111 or via email to mlahert@sultanlawyers.com.