Why doesn't my live USB boot partition show up as a 'Linux filesystem'?

I am trying to follow the steps on https://wiki.debian.org/RescueLive to recover my system which is currently not booting. I've created and booted a live version of Debian on a USB stick. However when I run fdisk -l from the terminal inside the live system I get the following output:

Disk /dev/sda: 57.62 GiB, 61872793600 bytes, 120845300 sectors
Disk model: DataTraveler 3.0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xccc4b779

Device     Boot Start     End Sectors  Size Id Type
/dev/sda1  *       64 6756479 6756416  3.2G  0 Empty
/dev/sda2        6804   16339    9536  4.7M ef EFI (FAT-12/16/32)

I expect the Type of /dev/sda1 to be Linux filesystem since that is the root partition but instead it is Empty. Following the steps in the RescueLive guide further I also run into the following issue when trying to bind mounts of /dev /proc and /sys:

root@debian:~# mount --bind /proc /mnt/proc
mount: /mnt/proc: mount point does not exist.
       dmesg(1) may have more information after failed mount system call.
root@debian:~# mkdir /mnt/proc
mkdir: cannot create directory ‘/mnt/proc’: Read-only file system

When trying to mount, the mount point doesn't exist inside /mnt but I am unable to create it!