The TP-Link UB500 Bluetooth 5.0 USB adapter is designed to add Bluetooth connectivity to a PC that doesn't have it natively, which would in principle allow a Bluetooth keyboard to be used with that PC. However, there are known compatibility issues with Windows 11. Several users have reported that the UB500 does not work properly on Windows 11, causing crashes when trying to add a Bluetooth device, whereas it worked fine on Windows 10.

TP-Link recommends downloading and installing the official driver from their website to ensure compatibility with Windows 11, but to date no fully stable Windows 11 driver has been released for this model, causing frequent malfunctions. Some users have had to revert to Windows 10 to get the adapter working normally again.

In short, if your PC is running Windows 11 Pro, it's likely that the UB500 adapter won't work properly to connect your Bluetooth keyboard, unless TP-Link publishes a compatible driver in the future. On Windows 10, this adapter would allow you to use a Bluetooth keyboard on a PC without built-in Bluetooth.

So, for now, adding this adapter to a Windows 11 PC does not guarantee that your Bluetooth keyboard will work properly.