Gentoo handbook grub2

gentoo handbook:amd64
gentoo efi variables are not supported on this system
grub2-install
gentoo handbook systemd
gentoo grub rescue
grub2-install target
gentoo parted
os-prober gentoo

GRUB2 replaces for the original GRUB Legacy boot loader with an entirely separate code See also What is the BIOS boot partition? in the x86 handbook. The GRUB2 article is huge and overly verbose in some places, GRUB2 Quick Start For example, the default UEFI command from the handbook is grub-install 34 Selecting a boot loader; 35 Default: GRUB2. 35.1 Emerge; 35.2 Install; 35.3 Configure. 36 Alternative 1: LILO. 36.1 Emerge; 36.2 Configure; 36.3 Install.