Internal mean, you are connected to your sata port from the motherboard, not usb / pcie.
when you boot from system recovery, and want to change something in the EFI partition, which mentioned in the UEFI troubleshooting, you should mount your /boot and /boot/efi partition first, as example :
$ mount /dev/xxx2 /mnt
$ mount /dev/xxx1 /mnt/efi
before mounting device, you should examine which drive and partition that hold /boot and /efi partition first by running
lsblk, /dev/xxx2 could be /dev/sda2 or /dev/sdb2 or /dev/nvme0n1p2, just make sure sda / sdb / nvme0n1 is the right drive.
maybe try run
efibootmgr -v first, have you found qubes os uefi entry there ?