System Rescue

If the system fails to start, the "Enable/disable rescue mode" feature provides access to the hard disk. 

The rescue environment relies on Rescatux. Once activated, boot into it and locate the original hard drive by executing the command:

lsblk

You should then see hard disk devices listed, such as /dev/sda1, that correspond to your disk's capacity (e.g., 50GB).

Next, simply mount the device to a directory like /mnt using the following command:

sudo mount /dev/sda1 /mnt

Perform any required modifications.

When finished, disable rescue mode.