The schools will see you as a White Canadian; they won’t care that your parents immigrated to Canada from Romania.
Your saga of switching high schools in order to find the right match won’t give you any advantage in admissions, no matter how it is spun, unless it were some noble, “how I overcame truly extraordinary adversity” story, and maybe not even then. At best, it will be neutral, no matter how you frame it. The schools will need to see transcripts from every high school you attended. They will calculate a GPA for you based upon your grades in your classes at each school. Your excellent SAT score will most definitely help your applications, but not enough to vault you into highly selective schools.
You are very unlikely to get into any highly selective schools in the US whose prestigious name might theoretically make them worth the high tuition, vs the fantastic value of Canadian schools for you. You might get into highly selective need-conscious small liberal arts colleges, who would view you as a full-pay student with high academic achievement. I’ve seen this happen with Middlebury. Others with more knowledge can weigh in on this for the other LACs. I don’t think that you will get into any of the Ivies, or any of the highly selective schools.
I would have killed for my kids to have had the chance to attend the best Canadian schools at the low tuition rates that Canadian residents get. Honestly, this is really your best option, by far. If you do well in a STEM field and want a PhD, you will then probably get into a lot of US graduate programs, with full funding. Save your parents over a quarter million dollars, and plan for undergrad in Canada.