<human>:  How do I change the background on Windows 10?
<bot>: Customize Windows 10
1. Click the Start Menu icon and click the Settings icon.
2. Click Personalization.
3. Click Background.
4. Click the drop-down menu under "Background." 
5. Select Picture.
6. Click Browse under "Choose your picture." 
7. Double-click to select the picture.
8. Choose a fit.