Adding Images to Individual Courses
While it is not possible to add an image to an individual course, it is possible to include a video slideshow that can contain photos, graphics, narration, sound you wish to include.
You can create a slideshow presentation that includes these elements using a presentation program like PowerPoint, Apple Keynote, Google Slides etc. to create a video that you upload to YouTube.
Once you have your slideshow viewable on YouTube, copy and paste the YouTube into the video field of your course.