If you are in high school in Ontario, your guidance counselor should know this better than I.
If you are a Canadian citizen or permanent resident, then to me your chances look very good. I am not familiar with programs for which admissions is particularly challenging (such as engineering or computer science or graduate programs), and I am not familiar with supplemental applications. However, when I and years later my two daughters applied to universities in Canada, as Canadian citizens or dual US/Canadian citizens, with a lot of A’s and not much else (at least for my daughters), we considered pretty much any university in Canada as a safety. This did not include the French language universities since none of us spoke French well enough, but we weren’t applying to them anyway. Between the three of us we were 9 for 9 on admissions (including two of us getting admitted to McGill – both getting our acceptance early) so I guess that “safety” was not all that far wrong.
To me “second generation immigrant” suggests that you were born in Canada, which along with your great grades should give you very solid chances at any university in Canada (not including French language universities). However, your guidance counselor would know better than I.