Hi @Claudia_O,
When it comes to customizing the "Help" area, you are limited to what is supported when following the How do I customize the Canvas Help Menu for an account? - Instructure Community - 127 support article.
When it comes to the "Search the Canvas Guides" link, in a supported way, I have the ability to edit:
- the name of the link
- the description of the link
- a few other things, such as who it is available to based on their role(s) in any courses
- when something is featured or new
- the headline
In a way that is supported by Canvas itself, it is not possible to edit the image.
If you were to use your web browser's inspect or developer tools, it is possible to find the source of the current image (it is an SVG file) and you might be able to (in a way that would not be supported by Canvas) change the image that is used but you would need to inject some sort of customized code to do it.
-Doug