How to start the desktop

Hi all,Thanks for having me on the forum. I have probably a very basic question but I cannot find the answer anywhere so sorry for the inconvenience.I downloaded the 2.8.4 version of LinuxCNC and used rufus to put it on usb stick. If i now boot my Beelink GK mini pc with it, I first see the LinuxCNC logo and after pressing enter the Debian startup screen. After a minute or so, I get into an ash shell BusyBox v1.30.1. But how do I now continue? I have no desktop. If i type help i get the standard commands like . : [ [[ alias bg break cd chdir etc, but no clear way to get further. Did the boot just fail? or do I have to type something? I already tried 'start' and 'linuxcnc', but these commands don't exist. At least not in the current search path.Thanks for anyone who can help me further. I have a bit of software skill, but I'm by no means an expert.Edit:I get an error message saying boot failed; unable to find a medium containing a live file system. Is that because it's on a usb drive and not a cd-rom? see attached photo for error message.drive.google.com/file/d/1cUfnK6B8aYbzyUK...PG0/view?usp=sharing

BUster won't know UEFI properly. Roll forward to Debian Bookworm.
docs.google.com/document/d/1jeV_4VKzVmOI...diY/edit?usp=sharing