That would probably be because early on they had tougher border controls and travel restrictions, unlike Canada. Also unlike Canada, much more ethnically homogeneous and the bordering countries are like minded in their methods for dealing with a relatively non-lethal virus. https://www.wsj.com/articles/finland-and-norway-avoid-covid-19-lockdowns-but-keep-the-virus-at-bay-11605704407

Norway's population is also only a few million with few large urban areas, and even these aren't exactly anthills and people can function in an orderly manner and survive by not flocking to mega stores in a panic.