There are a few things you need to know in order to fill a shape with an image in Illustrator. First, you’ll need to create a shape by selecting the Rectangle tool and choosing the Edit Mode. Next, select the Image option and click on the thumbnail of your image to open it up in a new window. Once you have your image open, use the arrow keys to move it around so that it’s in the right place and then press Enter. Finally, use the mouse wheel to resize your image so that it’s just right.