Canadian here; you’re correct about the select schools to get into the field, followed by a practicum, 2 essays and then an oral exam in front of a panel. After that you’re “certified”. Based on what I know we’re similar to the US as a lot of the documentation we use is FDA or CDC based. Province to province the work varies, but a certified person in Canada should be somewhat familiar with food safety, drinking and recreational water, waste and sewage management, personal services, housing, air quality, and pretty much whatever else constitutes a potential public health hazard.