Pages are blank slates for content generated using the Rich Content Editor. All pages in the Pages tool are versioned--which means you can roll back to a previous version of that page. To view or roll back to a page's previous version, click the vertical ellipsis icon 
located to the upper right of the page.
Since students can also be allowed to edit pages, they also serve as Wikis (online documents editable by several authors).
You may designate one page as your course front page, which allows it to be your course home page. The front page is also displayed first when you click the Pages link, after which you must click a second button to view the list of pages.
Instructure Guides:
When creating content in Canvas, you can use the Rich Content Editor, a WYSIWYG (i.e., what you see is what you get) editor for text, images, audio, and video. You can also use the Content Selector to insert files, images, or link to content, tools, and assignments already in your course or uploaded from your computer.
Instructure Guides:
Of course, some tasks (like inserting embed code) require an HTML Editor. The link that toggles from the Rich Content Editor to the HTML Editor is to the upper right. Check out the Canvas Guide about HTML view, or go straight to the Canvas HTML Allowlist.
