How do I find students' email address
The ability to see a student/users email address is controlled by a permission called (Users - view primary email address). I would recommend reaching out to your schools Canvas Admins to see if this is a permission they have enabled for the role in which you have inside Canvas.
I'll look into that, thank you for the tip.
Often you may get it when exporting the Grade book csv-file: How do I export grades from the Gradebook?
Retrieving data ...