90NB0CJ1-R31GE0 original Asus keyboard incl. topcase DE (german) black/grey with backlight

Unfortunately, this s not possible for multiple reasons:

• No manufacturer sells single key-caps, only whole keyboards. 
• There are way too many designs, holding-clips variants, color differences.
• There are multiple thousand different keyboards from different manufacturers.
• Sometimes even the same notebook model uses different keyboards
• Carrying that many different spare parts is almost impossible for manufacturers and sellers

You can only install keyboards intended for the use in your model. So, when your current keyboard does not have a numpad you will not be able to install one with a numpad, since they would be too large. The same is true for keyboards with numpad, ones without numpad would then be too small.

However, there is the option to use an external numpad connected via USB.

Most countries have their own keyboard Layout. Usually the device has the layout of the country it has been bought in.

The English layout can be recognized by the first six Characters of the top row of letters. That's also why it is called QWERTY-layout, another common abbreviation for it would be ENG-layout.

There can be multiple reasons for its failure.

• It could be an error in your operating system, for example, when the wrong input language is selected.
• The keyboard controller IC on the Mainboard could be damaged.
• Dirt, like food or dust could be stuck in the keyboard.