Long-press the app icon on the home screen
Tap Edit if available
Select the icon image you want
Choose from built-in icon packs or gallery, if supported
Save or apply the changes
If your launcher does not support icon changes, install a third-party launcher
Open the launcher settings
Go to Icon settings or Theme settings
Select the new icon pack
Apply the icon pack
If needed, use a shortcut app to create a custom icon for a specific app
Open the shortcut app
Select the app
Choose a custom image
Save the shortcut to the home screen