I'm including a lot of guest speakers and want them to have access to the course materials and chats with students.
It depends on how the Canvas admins at your school have set things up in Canvas. It's possible that you can go to the People tab in your course, click + People and enter email addresses of anyone such that it invites them to set up an account and join the course. But, while possible I know that most schools have that turned off.
I suggest you speak with your local Canvas admins to see if and how it's possible at your school. There are many issues regarding FERPA and privacy beyond the simple technical details of it being possible.
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