The link in the earlier reply is from when the Canvas Community was using a different platform. Unfortunately, when the Community site migrated to a new platform in the Summer of 2020, not all links migrated properly. You stumbled upon one of those links. The good news is that most of the time (but not always), you can use the search box at the top of any page here in the Community to search for the name of the document that is linked. Or, you can sometimes hover over the broken link and then look at the bottom of your browser to see where the link is pointing to so that you can get an idea of what the page name is/was.