Hi @Kerchove,
This is not something that's a built-in feature of Canvas, so I am assuming you're course is using some 3rd party system for textbooks. I am assuming you are a student, in which case you'd really need to reach out to your teacher or perhaps someone who may work at the bookstore or similar area at your school/institution.
I apologize that we can't give a much better answer than this.
-Chris
