Work with wireless accessories
Using Bluetooth technology, your MacBook Air can wirelessly connect with devices such as a Bluetooth keyboard, mouse, trackpad, AirPods, headset, peripheral devices, wearable sport accessories, and more.
Before you connect a Bluetooth device with your Mac for the first time, you need to pair them. When a Bluetooth device is paired with your Mac, you can connect or disconnect it using the Bluetooth 
menu.
Connect a Bluetooth device. Turn on the device so that it’s discoverable, then open System Settings and click Bluetooth. Select the device in the list, then click Connect. The device remains connected until you remove it. Control-click a device name to remove it.
Turn Bluetooth on or off. Click the Control Center icon 
in the menu bar, click the Bluetooth icon , then click the control to turn Bluetooth on or off. If you have the Bluetooth icon in your menu bar, you can click that and then turn the control on or off. Your MacBook Air comes with Bluetooth turned on.
Tip: If you don’t see the Bluetooth icon in the menu bar, you can add it. Click the Bluetooth icon in Control Center, click Bluetooth Settings, then select “Show Bluetooth in menu bar.”
Learn more. See Use Bluetooth devices with Mac in the macOS User Guide.