without chroot
[liveuser@localhost-live ~]$ efibootmgr
BootCurrent: 0001
Timeout: 0 seconds
BootOrder: 0005,0000,0001,0004,2001,2002,2003
Boot0000* Windows Boot Manager HD(1,GPT,c1bdfa82-dc3d-455b-a06f-1d4fb8afb2f1,0x800,0x32000)/File(\EFI\Microsoft\Boot\bootmgfw.efi)57494e444f5753000100000088000000780000004200430044004f0042004a004500430054003d007b00390064006500610038003600320063002d0035006300640064002d0034006500370030002d0061006300630031002d006600330032006200330034003400640034003700390035007d00000000000100000010000000040000007fff0400
Boot0001* Linpus lite HD(1,MBR,0x3eb3c,0x800,0x1d0d000)/File(\EFI\Boot\grubx64.efi)RC
Boot0002* EFI PXE 0 for IPv4 (98-FA-9B-02-A4-7D) PciRoot(0x0)/Pci(0x1d,0x5)/Pci(0x0,0x0)/MAC(98fa9b02a47d,0)/IPv4(0.0.0.00.0.0.0,0,0)RC
Boot0003* EFI PXE 0 for IPv6 (98-FA-9B-02-A4-7D) PciRoot(0x0)/Pci(0x1d,0x5)/Pci(0x0,0x0)/MAC(98fa9b02a47d,0)/IPv6([::]:<->[::]:,0,0)RC
Boot0004* Fedora HD(1,GPT,c1bdfa82-dc3d-455b-a06f-1d4fb8afb2f1,0x800,0x32000)/File(\EFI\fedora\shim.efi) File(.䍒)
Boot0005* Fedora HD(1,GPT,c1bdfa82-dc3d-455b-a06f-1d4fb8afb2f1,0x800,0x32000)/File(\EFI\fedora\shimx64.efi)
Boot0009* EFI PXE 0 for IPv4 (98-FA-9B-02-A4-7D) PciRoot(0x0)/Pci(0x1d,0x5)/Pci(0x0,0x0)/MAC(98fa9b02a47d,0)/IPv4(0.0.0.00.0.0.0,0,0)RC
Boot2001* EFI USB Device RC
Boot2002* EFI DVD/CDROM RC
Boot2003* EFI Network RC
[liveuser@localhost-live ~]$
[liveuser@localhost-live ~]$ efibootmgr
BootCurrent: 0001
Timeout: 0 seconds
BootOrder: 0005,0000,0001,0004,2001,2002,2003
Boot0000* Windows Boot Manager HD(1,GPT,c1bdfa82-dc3d-455b-a06f-1d4fb8afb2f1,0x800,0x32000)/File(\EFI\Microsoft\Boot\bootmgfw.efi)57494e444f5753000100000088000000780000004200430044004f0042004a004500430054003d007b00390064006500610038003600320063002d0035006300640064002d0034006500370030002d0061006300630031002d006600330032006200330034003400640034003700390035007d00000000000100000010000000040000007fff0400
Boot0001* Linpus lite HD(1,MBR,0x3eb3c,0x800,0x1d0d000)/File(\EFI\Boot\grubx64.efi)RC
Boot0002* EFI PXE 0 for IPv4 (98-FA-9B-02-A4-7D) PciRoot(0x0)/Pci(0x1d,0x5)/Pci(0x0,0x0)/MAC(98fa9b02a47d,0)/IPv4(0.0.0.00.0.0.0,0,0)RC
Boot0003* EFI PXE 0 for IPv6 (98-FA-9B-02-A4-7D) PciRoot(0x0)/Pci(0x1d,0x5)/Pci(0x0,0x0)/MAC(98fa9b02a47d,0)/IPv6([::]:<->[::]:,0,0)RC
Boot0004* Fedora HD(1,GPT,c1bdfa82-dc3d-455b-a06f-1d4fb8afb2f1,0x800,0x32000)/File(\EFI\fedora\shim.efi) File(.䍒)
Boot0005* Fedora HD(1,GPT,c1bdfa82-dc3d-455b-a06f-1d4fb8afb2f1,0x800,0x32000)/File(\EFI\fedora\shimx64.efi)
Boot0009* EFI PXE 0 for IPv4 (98-FA-9B-02-A4-7D) PciRoot(0x0)/Pci(0x1d,0x5)/Pci(0x0,0x0)/MAC(98fa9b02a47d,0)/IPv4(0.0.0.00.0.0.0,0,0)RC
Boot2001* EFI USB Device RC
Boot2002* EFI DVD/CDROM RC
Boot2003* EFI Network RC
[liveuser@localhost-live ~]$
with Chroot
[liveuser@localhost-live ~]$ su
[root@localhost-live liveuser]# mount -t btrfs -o subvol=root,compress=zstd:1 /dev/nvme0n1p6 /mnt
[root@localhost-live liveuser]# for file in sys run proc dev ; do mount -o bind /$file /mnt/$file ; done
[root@localhost-live liveuser]# chroot /mnt
root@localhost-live:/# efibootmgr
EFI variables are not supported on this system.
root@localhost-live:/# mount -a
root@localhost-live:/# efibootmgr
EFI variables are not supported on this system.
root@localhost-live:/#