You are welcome
Actually, the overheating hypothesis is the very last one to be checked as it is remote.
We should check if it's a system or keyboard problem.
Do you have another usb keyboard handy
Plug in a USB keyboard to your laptop,
just to check if it's a keyboard problem or a system problem,
If the USB keyboard, all keys working means there's a problem with your keyboard
You will have to replace to a new one
If the usb keyboard also causes a problem, we will look into the system.