Failed to save boot record. Need new boot record

Installed latest xfce desktop.
Asked saving boot record on usb flash drive.
Operation failed. I can not boot from HD the Calculate now.

How can I save new boot record
either on usb stick
or hard disk with EFI structure?

I have live CD.

I could not find any info about initrd creation at Gentoo.

What a distro !!
there is nobody to answer.
there is no documentation to guide !