make /home max possible size

Hi, I going well with the help of cPanel in managing Linux servers, as my experience is in windows hosting. I don't understand how linux deals with partitions, as there is no C:/ or D:/ as I see. I've a new server with HDD:

2x HDD SATA 4,0 TB Enterprise

how can I set the /home partition to be the maximum size before installing cPanel, when I install cPanel from server from OVH I found the home partition max. size /dev/md2 3.7T
from Hetzner, I found 2 partitions /dev/md2 2.0T & /dev/md3 1.7T
is there a command I can use before installing cPanel, makes /home the max. possible?