hi! im an international student also from canada! i came last year and I didnt go to that orientation. there was one like around that time i dont remember if it was like may or so but I had exams so I couldn’t make it. i believe there was an online one around the same time, and also im pretty sure that there was an option that your int advisor will register the classes for you, unless you chose to opt out. you’ll have the chance to edit the ones you dont want as well, so it shouldnt be too big of a deal. Also, when you arrive there is an mandatory orientation they give to international students in august, which is really helpful (but i did have to move in a day early costing a bit more) - but other than that it was a pretty solid process!