To add an image on a slide, go to "Insert" in the upper settings menu of the editor, then Media, and select Photo. If you are using a template, images will be already added. To change a picture, just click on it.
In the pop-up window that shows up, you can search using keywords to find images related to what you need. On this window, you can also browse for Icons and Gifs from our integrated galleries, or Upload your own images.
In the Design editor, you can manually drag and drop the images to resize and reposition them. You can also use the auto-alignment.
To edit a photo, just select it. Images can be cropped in three different Styles: Fill, Contain, or Circle. This will affect the image frame and the caption positioning. The Crop button over the image allows you to reposition the picture on the crop frame.
To Delete an image, click on it and look at the bottom of its editing options. In the Outline editor, just hover over the image element and look for the Bin icon displayed in its top right corner.