Hello @lachlanwintour ...
What do you mean by the word "sites"? That is not any Canvas terminology that I am familiar with. Do you just want to create several course shells in Canvas so that you can add course content to each of them? If so, and if you are a Canvas administrator, then you can do this by following the steps in this Guide: How do I add a course in an account as an admin?.
There are also ways to create Canvas course shells via SIS Import. Here are a handful of Guides that will help you along the way (again, these are Canvas administrator Guides):
I hope these resources will be of help to you. Please let Community members know if you have any other questions about this...thanks! Take care, stay safe, and be well.