If you go to the Department of Astronomy and Astrophysics web page, and click on "Undergraduate", then click on "Information for prospective UofT students", then click on "High School Students" right under the heading "Information For", it will take you to a page that says:
"Are you a high school student considering applying to Arts and Science?
Check out these pages for all the information you need about admission requirements and the application process."
If you click there, you can click on the right hand column for information depending on whether you come from Ontario, other provinces, the US, Britain, etc. It has an attached PDF file that describes what requirements are required in addition to English. (e.g. Physics and Calculus)
This took me less than three minutes to find. If you couldn't find this yourself, even with prodding, I think you will have difficulty in college. College requires both a certain degree of self-sufficiency and a certain facility with finding information.