One thing that I might have hinted at above but that is worth saying very clearly: Your highly competitive private high school is full of very competitive students. However, they are high school students. They do not have extensive experiences in life. They do not necessarily know what is needed to attend highly ranked universities, nor to do very well in life. Take whatever they are doing and whatever they are saying with what we in North America might refer to as “a grain of salt”, meaning do not assume that you need to get caught up in the highly competitive race. Take things at your own pace and trust that this will work out one way or another.
You do not need to take any classes outside of school. Macroeconomics for example was something that I took as a university student. You really can wait and take this after you get to university, or just not take it at all (depending upon what career you end up being interested in – for international relations it does seem like a course you should take at some point, but that point does not need to be when you are in high school).
If you are interested in economics, I might add that I was a math major who took one single non-math elective in graduate school, which was econometrics. There is a lot of math in econometrics. Even as a math major it had me spending a Saturday afternoon making sure that I remembered my linear algebra well enough to handle the class. Apparently multi-variate calculus also shows up in economics, and probability and statistics also seem quite relevant. As a person who might major in a field that draws somewhat upon economics, it might also be useful to take math classes quite seriously (although it sounds like you are already doing this). I by the way liked econometrics quite a bit partly because to me it seems to start to take economics out of the “my opinion, your opinion” area into something that can be quantitatively verified.
You do not need to take the SAT exam as a sophomore in high school. It is way more usual to take it towards the end of your junior year or the beginning of your senior year of high school. Some take it over the summer in between. While your English appears to be excellent, if English is not your first language it is likely to be even stronger when you get to your junior and senior years of high school compared to right now.
With your coming from Ukraine, currently living in Canada, and thinking about universities in the US, another issue comes to mind: Where do you intend to end up living ten or twenty years from now? Attending university in the US will not allow you to stay in the US after graduation. Normally international students who graduate from university in the US are required to return to their home country, or at least somewhere outside the US, after graduation. Also, at least in my experience Canadian employers seem to prefer to hire graduates from the excellent universities in Canada rather than hire Canadians who graduate from universities in the US, even top ranked schools. There is understandably at this point a great deal of sympathy for Ukrainians in both the US and Canada, but none of us can know at this point whether this would help you to be allowed to live in the US after graduation. This is a largely political issue and politics in the US (and probably elsewhere) is very difficult or impossible to predict far in advance.
I will admit that I very much hope that well before you graduate university the war in Ukraine will end with Russia completely leaving Ukraine and going home. Hopefully this will allow you to return to Ukraine and help with what is likely to be a huge rebuilding effort, if you choose to do so. However, this is again something that is very hard to predict in advance.
If your intention is to end up in Canada long term, it might be a better plan to get your bachelor’s degree in Canada, and then think about whether you want to get some form of graduate degree in the US. This would allow someone taking a cursory look at your resume to at least see some connection to Canada at first glance. I used to know or work with quite a few people who did this, including two people who got their bachelor’s in Canada and then got a master’s at Stanford, and one person who got their bachelor’s in Canada and then got a master’s and a PhD at Princeton. I also have known several people who got their graduate degrees (or is currently getting their degree) at other very good universities in the US after getting a bachelor’s in Canada, and I know one person who went the other way (bachelor’s in the US, law degree in Canada).
Fortunately you have a lot of time to think about this. To me it looks like you are doing very well right now.
And best wishes for you and for Ukraine.