I have an Asus rog laptop, have been trying to get the backlight to work again after i reinstalled endeavour os, I honestly do not remember exactly how I got it working in the first place. I remember I used rogauracore but that seems to not solve the issue right now. I have also tried xset to no avail.
Any help would be appreciated, thanks!
For keyboard backlight:
Have a look in /sys/class/leds
You should have some folders that have ‘kbd’ in the name.
Look in those folders for a file called brightness, and set it to your maximum (mine was 3)
For screen backlight:
Have a look in /sys/class/backlight, and find the backlight folder that corresponds to your PC (mine was intel_backlight)
HTH