I just installed BURG, but during the installation I made a mistake: after the package was installed, I got to some command-line based GUI for configuration, where I forgot to mark my (only) hard disk as the boot device before I hit OK. I tried to reinstall (apt-get purge burg && apt-get autoremove followed by apt-get install burg) but I wasn't able to get to the same screen again (I didn't find the GUI).

When I now start my computer, I am taken to a GRUB2 prompt and no BURG (or GRUB2) boot menu is shown. Since I don't know any GRUB commands and I am helpless.

How do I reinstall GRUB/BURG correctly?

Update: I rebooted my computer, and got a BURG prompt (which appears to be the same thing as a GRUB prompt, but if there's a difference I wouldn't know it...). I have booted from a Live USB, but I don't know what to do next.

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