Who would hire me after I get out of college with a Biology degree? Due to my British citizenship, would I not get it after 4 years or less?
But the British government might and the immigration service could refuse to issue you an exit permit or any other documents required to get your H1B or J1 visa.
PR/citizenship isn’t automatic after living in Canada X amount time, nor is it automatic for being a resident of a Commonwealth nation. You have to have a work permit and be employed full time in a worker shortage field for at least 1 year before you’re eligible to apply for your PR. Once you have your PR in hand (and paperwork takes time to work its way thru appropriate channels), then you could apply for medical school–a process that takes a full year in itself, just like it does in the US. So at a minimum you’d have 2 or 3 years post college graduation before you could start med school.
BTW, admission rates to Canadian med schools are much lower than US med school admissions rates due to having fewer seats and having most seats restricted to in-province residents only.
Also for Canadian PR/citizens who wish to do their residency training in the US, you need written permission from your provincial government. If it’s granted at all, that permission comes with a Return of Service contract that requires you to return to Canada and serve as a physician in a medically underserved region within your home province for 3-7 years. (varies by province and specialty)