Open the keyboard app you use
Go to Settings
Tap Theme or Appearance
Select Wallpaper or Background
Choose an image from the gallery or gallery folder
Adjust the image...
Open the keyboard app
Go to Keyboard settings
Tap Themes or Wallpaper
Select a wallpaper source
Choose an image
Adjust the crop or position if needed
Tap Set or Apply
Enable...
Check whether your keyboard has RGB or backlit lighting
Locate the keyboard lighting key or shortcut
Press the lighting key or use the Fn key combination
Use...
