How would I install a different copy of linux on a old laptop?

Question

TLDR; I am trying to install a GUI version of Linux on an old laptop with Ubuntu Server already installed, but get a grub error when I boot. How can I get past this problem.

error: file '/boot/grub/i386-pc/normal.mod' not found.

Entering rescue mode...

Current Linux Version: Ubuntu Server 22.04.3 LTS

New OS: Linux Mint 21.2 64 bit (disk image on USB)

I installed Ubuntu Server 22.04.3 LTS on my old laptop.

The intention was to back up all my photos onto a home server.

Now, I want to install a Desktop version of Linux on it.

I have tried to research and ask some some friends, but I am just not knowledgeable enough about the subject to understand.

What can I do/investigate to move forward? Please treat me like a 7 year old, when I see 'grub' I think of an insect in the ground.

Answer 1

The bootable USB isn't created correctly, you can create a bootable USB through the mkusb utility (GUI and command line).

Ubuntu help:

dus-iso2usb (command line)

This makes a system that can boot via grub into an iso file both in UEFI mode and BIOS mode (alias CSM alias legacy mode), 'grub-n-iso'.