To add objects to the slide you can proceed in two ways:

Use the shortcut bar at the bottom

This is the easiest way and the one you use primarily. Just click on the icon corresponding to the object you want to see appear in the center of the slide. You can then modify it according to your wishes.

Drag and drop items from Windows

You can also open a standard Windows Explorer, select one or more images (or videos) and move them to the slide you want.

Similarly, you can select other objects in other applications (text, Excel charts, etc ...) and place it directly on the target slide.

When you select multiple images and you put them down on a slide, they are all added to the current slide. If you want to create a new slide by photo, then use this feature: import a folder of images automatically .