Click the Start menu and navigate to Settings > Control Panel >
If you are using Classic View then click on "Personalization" and select the "Screensaver". If you are using Category View then click on "Appearance and Personalization" and then select "Change screen saver".
Select another screensaver from the drop-down.
To remove your screensaver:
Click the Start menu and navigate to Settings > Control Panel
Click "Uninstall a program"
Select the screensaver that you want to remove and click the "Uninstall" button.