Talk to your Career Center at USC. They can help you apply for internships abroad and help confirm eligibility.
As a Canadian Citizen you are allowed to work in Canada. Do you have a Canadian Social Insurance Number already? (you should). That is all you need, as well as proof of Canadian Citizenship.
Note, some provinces, like Ontario, have a 3 month waiting period before you are eligible for Provincial Health Insurance, so you will need private health insurance. (or maybe your parents insurance plan will cover you?)
Talk to USC career center, they will help.