Backlight keyboard issue

[Ponce-De-Leon]

You could try this:

Can't turn on keyboard backlight on Asus Laptop

Have you yet tried the Grub Parameter acpi_backlight=vendor? Be sure to remember to run sudo update-grub after changing the grub file.

or this:
https://askubuntu.com/questions/1412055/keyboard-backlight-in-ubuntu-22-04

Another Option would be to take a Look at OpenRGB:

OpenRGB