First of all, congratulations! Getting a school admission is always good news. For an international student, that means you can start your application for an official immigration permit to study in Canada.
If you are admitted into a school located in any Canadian province other than Quebec, you can immediately apply for your student visa or study permit. Here is the direct link to the Immigration Canada website to submit your application.
If you are admitted into a school located in Quebec, you will follow a two-step process. Before applying for your study permit as described above, you first need to submit your application for temporary selection for studies (CAQ). Here is the direct link to the Quebec Immigration website to submit your application.