PC keyboards with and without cable
The keyboard layout in Germany is standardized ("qwertz"), the design is a matter of taste. You only have to decide on the color and the type of connection: cable or not cable?
Keyboards with a cable (usually about 1.5m) are plugged into a free USB port nowadays; old PS2 ports are hardly supported anymore.
Wireless keyboards send a radio signal (loosely based on the BlueTooth standard) to a small receiver that plugs into a free USB port. All current PCs (and almost all older ones) already recognize this receiver at BIOS level right after the computer is turned on; without this feature, UEFI technology would be pointless. Drivers are only needed for special features and are immediately installed by all operating systems. If you remember the first wireless keyboards and the effort that was necessary to install them, you can now sit back and enjoy the freedom from cables!
The only small drawback is that the mouse and keyboard have to be fed with new batteries 1-2 times a year - unfortunately, rechargeable batteries don't work because of the lower voltage (1.2 instead of 1.5 volts). Since the batteries stay in the devices for a long time, you should absolutely use leak-proof alkaline types.