While traditional copyright protections can get in the way of including paywalled articles in your Canvas shell, there is a lot of research available to you right now for immediate course use:
If you find something in an open repository, published by an open access journal publisher, or published by the government, you can feel free to incorporate them into your course once you verify the access specified in the license. Or, in the case of materials in the public domain, use it however you like!