Every Linux has Dig in on each of their home/official site e.g: https://www.gnu.org/software/grub/manual/grub/grub.pdf https://www.gnu.org/software/grub/manual

Every Linux has Dig in on each of their home/official site e.g: https://www.gnu.org/software/grub/manual/grub/grub.pdf https://www.gnu.org/software/grub/manual/grub/grub.pdf most say Gentoo or Funtoo (its improvement) excel in docs. among them