Both those are USB peripherals, they can only communicate with a USB host (a root hub). What you require is a device between the keyboard and the bluetooth which can do what you tell it to.

In recent years, many PC peripherals have adopted USB or Bluetooth to connect to PCs, but until USB became mainstream in the mid-2000s, connections via PS/2 connectors were common. Raymond Chen, a ...

The compact, smooth-operating K380 is a desktop wireless keyboard replacement that connects to up to three devices -- including tablets and phones -- and allows you to toggle between them.