If your keyboard keys stop working, it doesn't necessarily mean they're broken or need replacement. From checking keyboard ...

If your keyboard and mouse are not working, you must clear CMOS to reset your BIOS. Open your laptop and remove the CMOS battery. Wait for a few seconds and insert the CMOS battery again.

Follow the steps if you have TeamViewer installed on your PC: Computer keyboard keys can fail to work if there is debris between them. Other reasons for some buttons not working on your keyboard ...