Want to change your desktop background (wallpaper)? That’s to say, the main picture on your PC screen. Go to Start, then Settings and then Personalisation.
In Lock screen, select a picture.
And because it’s Halloween coming up (when this page was originally written), try using these Halloween themed images as your desktop image, or lock screen.
Left click the image, then choose ‘Save image as’, and save it in your chosen place. Then follow the instructions at the top of this page.
Halloween theme Windows icon
You can also right-click on your desktop, and choose ‘Personalise’, and then follow the above instructions.
Halloween LGBT theme
TIP: Don’t use an image for the lock screen or desktop background that you could be embarrassed about. So perhaps no cute cats, or even cute naked men or women. If your PC needs repairing, these are usually the first screen the technician sees.