I assume these are the partitions you made for your EnOS install.
In the live session, make sure you have network connection.
Open a terminal and run the following commands:
sudo mount /dev/sda7 /mnt
sudo mkdir -p /mnt/boot/efi
sudo mount /dev/sda6 /mnt/boot/efi
sudo arch-chroot /mnt
pacman -S grub
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=enos-grub
exit
Now check with efibootmgr to make sure an EFI boot entry has been created.
If you get any errors at any of the steps above, please post it here.
And please don’t forget to format the posted text by highlighting it and pressing Ctrl-E.
EDIT: correction
sudo mkdir -p /boot/efi should be sudo mkdir -p /mn/boot/efi
Sorry for that 