MacBook Air 2018 keyboard not working or lighting up

I am sorry to hear that your keyboard is not working. Please try this

If no keys work on your Mac notebook computer’s built-in keyboard

• Your Mac may be showing a low battery alert that you can’t see. Connect your Mac to an electrical outlet or connect an external keyboard to your Mac to see the alert.

If the Media Eject key or Caps Lock key doesn’t work

• Try holding down the key longer. These keys have a slight delay to prevent an immediate response if they’re pressed accidentally. Press and hold the Media Eject key until the Media Eject icon appears on the screen, and press and hold the Caps Lock key until the key’s indicator light comes on.

If other keys don’t work

You may have accidentally set an option that changes how your keyboard operates.

• Choose Apple menu  > System Settings, click Accessibility  in the sidebar, then click Keyboard on the right. (You may need to scroll down.) Make sure Slow Keys is turned off. If Slow Keys is on, you must press and hold a key longer than usual before it’s recognised.
• Choose Apple menu > System Settings, click Accessibility in the sidebar, then click Pointer Control on the right. (You may need to scroll down.) Make sure Mouse Keys is off.
• Choose Apple menu > System Settings, then click Keyboard  in the sidebar. (You may need to scroll down.) Click Edit next to Input Sources on the right, then turn on “Show Input menu in menu bar”. Open the Input menu, then make sure the correct keyboard layout is selected.