Go to Control Panel click it then click Programs and Features.
Click Turn Windows Features on and off
at top left.
The above blue is a link to the tutorial I didn't know we had.
New window check mark Windows Gadget Platform.
Picture below shows both with yellow circle.
Also you will see Games etc. listed. Good to remember for future use.
Bonus tutorial how to use gadgets once you turn it on. Gadgets - Add or Remove from Desktop
Click the picture below to enlarge.