My PC was OFF when my UPC battery failed. However, when I booted up the screen came up into "grub rescue>" mode.

grub rescue> set yields:
cmdpath=(hd0)
lang=
locale_dir=
prefix=(hd0,msdos1)/boot/grub
root=hd0,msdos1
secondary_locale_dir=

I tried grub rescue> intmod normal:
error: symbol 'grub_calloc' not found
I tried grub rescue> boot
error: you need to load the kernel first (I believe the latest kerrnel is linux 5.8.0-38 generic)

I am unable to get to the regular Terminal screen to update or upgrade Grub.