Canvas has an entire page of various tutorials at the link given below. However, you do NOT have to sign up for a Canvas account (the first guide listed) as all Dominican students who have registered for a class should have a Canvas account created for them automatically. This page has both text-based guides and video overviews: Getting Started as a Student. Be sure to scroll down a bit to see the video links.
Especially recommended if you are completely new to Canvas is a video overview of all areas this available here in their Canvas Overview for Students.
A complete online Student Guide to Canvas is also available, though can be a bit intimidating! It is arranged by broad area of topic, but is also keyword searchable. It is available here: Canvas Student Guide.