As the author or creator of the work, you likely own copyright in it unless you have assigned (i.e., transferred) ownership of copyright to someone else such as a publisher.
If you own copyright in the work you can use it in any way you like, such as posting it in your Canvas course, including it in a course pack, or handing out copies in class.
If you transferred copyright to a publisher or another party, you can copy the work within the limits on the Copyright and Teaching infographic or contact the copyright owner to request permission to use it.