Sometimes when we have used a laptop for a few years, its keyboard starts to wear down. Some of the keys get stuck, some of the keys are no longer doing anything, and if it is also possible that the whole keyboard stops working. This is also true for keyboards designed for the desktop computers.
There are many different reasons for this to happen, but almost all of them are related to the hardware damage. When you have used your keyboard a lot, the membrane based contacts inside the keyboard wear out or even get broken.
If you are not sure whether your keyboard keys have become damaged then you can test your keyboard easily using an online web app by visiting https://en.key-test.ru/.
The website displays a full sized 101 keys keyboard. As you press keys on your keyboard, the website keyboard lights up the pressed keys. For example, if you press the Left Shift key on your physical keyboard then you will see the “Left Shift” key glow up on the key test website.
If you think that the problem has something to do with the drivers or operating system, then you can boot using Live Linux CD or USB drive and repeat the same steps.
You can press all the keys on your physical keyboard and see which of the keys are not glowing up on the website keyboard. Those are the keys that are not registering on your operating system. These keys could be faulty. If this happens, you can visit your local computer shop and have your keyboard repaired.
If it is a laptop keyboard, then you have to get it repaired or replaced by professionals. If it is a desktop keyboard, then it can be replaced easily and you can buy a new desktop keyboard from any online store such as Amazon.