You can use a picture as backgound for your slides in a PowerPoint presentation. If the picture is from the internet, you need to download or save it to the desktop or your Documents folder before it can be used in the presentation.
To save the picture, hold the control key on the keyboard and click on the picture.
Then select Save image to "Documents"or Save image to the Desktop from the dropdown menu.
To use the picture as the slide background:
1. Open a PowerPoint presentation.
2. Click on Format -- Slide Background.
3. In the Format Background window, be sure the Picture tab is selected. Next, click the Choose a Picture button near the bottom of the window.
In the choose a Picture window, navigate to your Documents folder (or the desktop) and select the picture you are using as the background, then click the Insert button.
Back in the Format Background window, click the Apply button. The picture will now show in the slide background. (Click the Apply to All button if you want the picture to be applied to all of the slides in the presentation).