Hello @eleczn ...
If you are the instructor of a course in Canvas, you can easily get a count of students and other roles by looking at a chart available on the course "Settings" page. When you click on course "Settings", on the right side of the screen, you'll see a chart with a heading of "Current Users" which will show you a count of users broken down by role.
Does this help in getting some/all the information you are looking for?
