I've picked up an old computer my grandma used to have, and put another hard drive in it so I can use it as a media server. I wanted to install Ubuntu because I'm just following a tutorial, but I've run into an issue which I believe is being caused by the bios. Before I even installed Ubuntu, I had issues. The computer would boot, get past the splash screen, then ask my keyboard layout. As soon as I used the keyboard, the computer froze. So I tried entering bios from the splash screen. Same result, freezing as soon as I touch the keyboard. I put Ubuntu on a flash drive and started the installation. The first time, I pressed enter on the keyboard to select, and to no surprise, a freeze happened. So next time I waited out the 30 seconds and the installation went fine, went into the live environment, etc. I got Ubuntu installed on both of the drives just in case. When I restart the computer, a screen saying this comes up and I can't do anything, even after another restart.
"Reboot and select proper boot device"
"Or insert boot media in selected boot device and press a key"
I can't get any further than this, I suspect it must be a corrupted bios/bios error, but I'm not entirely sure. Any help is appreciated!
Edit: Computer is an HP Pavilion p6803w, running an Athlon II X2 Dual Core 220 with 4gb of ram, which meets the requirements of Ubuntu 22.04.1 LTS, which I'm trying to install.
Edit 2: I've tried installing both Xubuntu and Ubuntu server, and neither worked.