Installation Problem "/dev/root does not exit"

I never installed any Linux before so if this is something totally obvious, I’m sorry! :sweat_smile:

I followed to installation guide from tecmint

I downloaded “AlmaLinux-8.6-x86_64-dvd.iso” from here and made a bootable USB device with UNetbooting.

When I boot the PC I get the page where I can choose to install Alma.
The first few lines that appear look quite ok i guess?

Then a lot of similar lines will appear ( the first number is changing with each line)

[147.289847] dracut-initqueue[1059]: Warning dracut-initqueue timeout - starting timeout scripts

After that:

[like above] Warning: Could not boot.
Starting Setup Virtual Console..
[OK] Started Setup Virtual Console.
Starting Dracut Emergency Shell...
Warning: /dev/root does not exist

Does anybody has an idea what I did wrong? Or do you need more information?