Hello,
If only a few keys don't work, this is typically hardware issue.
Underneath the keyboard, there is a circuit board with numerous signal tracks. Cracks in the tracks, dust or debris buildup, or corrosion can disrupt the signal flow.
Does the esc key work from the on-screen keyboard?
Hello, this is Emily.
The onscreen keyboard doesn't have F keys, but you can test with a different keyboard via USB or Bluetooth. If the alternative keyboard works, it's certain that the issue is hardware-related.
You can try to clean the keyboard, but if it is cracks or corrosion, cleaning will not help unfortunately. You need hardware repair or replacement.