Head to Settings > Devices > Bluetooth & other devices, then click the toggle to make Bluetooth Available. You can also jump to the Quick Settings menu with the shortcut (Win + A). If your PC does not already have Bluetooth, connect a Bluetooth adapter for use. As a result, you can wirelessly control audio, use input devices and send files between your gadgets and your PC.
For more read - https://datarecovee.com/how-to-turn-on-bluetooth-on-windows-10/