- Make a bootable device of the distribution you are using(debian,kali,ubuntu)
- Open the terminal
- Type
lsblk
to list the various blocks of the hard disk
root@sperixlabs: ~# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 931.5G 0 disk
├─sda1 8:1 0 526.5G 0 part /