It looks like grub can not find the root partition. I have seen this happen before after installing Debian 10, but am not entirely sure what causes it. However, I can tell you how I fixed it.
In grub rescue:
1.) list available partitions:
ls
- this will list the disks and partitions.
2.) on outputs that are written as a tuple, with the form
(hdX,msdosX) or (hdX,gptX), you want to list each of these to find out where the linux partition is (this will contain, among other things, "vmlinuz").
- To do this use:
ls (hdX,msdosX)/ on each of the partitions in that tuple form.
3.) set the linux partition to root:
- Commands:
set root=(hdX,msdosX)
set prefix=(hdX,msdosX)/boot/grub
4.) insert module on kernel:
insmod normal
5.) restart the machine:
normal
After rebooting, Debian worked fine for me.
My reference for the answer:
https://gnu-linux.org/grub-rescue-commands.html
Another response to a similar problem:
https://askubuntu.com/questions/397...pt-to-read-or-write-outside-of-disk-hd0-error
