When you edit the wiki, you can add images, but they must have already been uploaded to the channelYou can add an image to a wiki page. The image must first be stored in the wiki by uploading it to the wiki.
In the center panel, click the spot where you want to insert the image, and then click the image icon. Image Modified
A Pick a File dialog box opens. It only shows images that have already been uploaded to the wiki. Image Modified
Select the image file that you want to insert.
Click Pick File. The image file appears in the text editor in the format shown below. You may change the text My_Image to something more descriptive for a screen reader or for reference. The Preview panel shows how the image will appear in the wiki. Image Modified