If you'd like to add an image to a content area simply click the IMAGE ICON (see circled icon below) to open.

A box will open.  The "General" tab allows you to source the image from the web.  For example, if you have an image from your own website you'd like to use, simply open the website, right click on the image, and get the URL address for that image.  That is your "source".  As you can see below, you can change the dimensions if you'd like.

Or, you choose the "Upload" tab, browse for the image on your computer or drag and drop the image into the box.