Do you really need a dongle? The keyboard has normal Bluetooth. That means you can connect it to the Bluetooth module of your laptop. If you have a newer device, you can try this via "Add device" on Windows 10. 1.
1. press the Windows key
2. type "bluetooth" on the keyboard
3. open the corresponding system setting with confirmation of the displayed selection
4. click on "+" Add Bluetooth or other device

For Windows Hello you must then also install a driver https://www.microsoft.com/accessorie...

If your device really does not have a Bluetooth module integrated, you can buy any dongle that supports Bluetooth 4.0, Bluetooth LE, or Bluetooth Smart.