Busybox Debian commanding

[Gunnar Gervin]

Hi.
My computer is in
grub rescue>
Crisis mode.
Busybox (ash) commands only option to recover the machine w/Debian "Buster"
i386mac32b.
Tried to remove all 7 partitions in grub rescue>
(hd0,gpt1 to hd0,gpt7)
 4 partitions in ext2, 3 unknown), with Bash, but no success.
Which(in exact form)commands
Busybox command to unmount & delete "unknown" partitions?
Which commands delete th rest?
Gunnar