Its difficult to gauge your chances at T20 colleges without knowing your class rank and test scores. Even if your HS does not rank, the colleges can usually estimate it. So start there.
If your class rank is outside of the top 5% then your road to a T20 acceptance will be very difficult. Many of the T20 colleges will offer aid to internationals, but it will be based on need (as they define it), not as how your parents will define it. The tuition/fees for these schools can run upwards of $320K USD for 4 years. Are your parents willing to shell that out? You could buy a decent house for that amount of money.
If money is no object then I’d start by doing the following
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Take harder courses. An unweighted 3.6 and weighted 3.61 indicates to me that you aren’t taking the honors/AP level classes in your high school. You’ll need to have high GPA with good rigor to have a chance.
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Get your grades up. The colleges do take upward progression into account.
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Study for the ACT/SAT. You’ll need high scores. Roughly 1500 for SAT or 33 for ACT will put you in the best shape. It doesn’t guarantee anything of course. But without this, you’ll face an uphill battle.
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Start working on a cohesive narrative about yourself. You want to portray yourself to the admissions committee that will stand out from the pack. Right now I see a mish-mash of different activities. Its hard for me to understand where you might fit into an incoming class.
If you decide to stay in Canada, you might also consider doing a semester/year abroad in the US. There is also the option of doing a post-graduate year at a US boarding school before starting college. You might also consider UK universities.