site i used to learn this
https://www.cherryservers.com/blog/how-to-partition-and-format-disk-drives-on-linux
started a new project that i needed to add another storage device to
first in proxmox created and added a 1tb virtio block in the vm hardware interface "patiently wait it took some time created from my plater mirror zfs pool"
then in the vm fdisk -l find your new disk there wont be any partition probably be the lowest on the list looks weird when you look at it for first time also the device shouldnt have a number next to device /vdb if partition is found it would have a number /vdb1 to say how many or list of paritions on drive
mine was labled /dev/vdb
then you can run fdisk /dev/vdb
that will prompt to ask to install mbr i wanted gpt and hit the m for help and saw g for gpt
so you hit g enter that will create it then hit enter to accept the defaults then w to write the changes
then use mkfs.ext4 /dev/vdb1 to create a ext4 partition
now to mount that create a location i made mine /cache
then mount
mount -t ext4 -o rw /dev/svdb1 /cache
then ls /cache
should have lost&found in there and you can try to make a file or folder to test access but i think it will be fine i was more worried about automount on reboot
now on to automount in /etc/fstab
type blkid to find the uuid
i use nano as its a very simple text editor that tells you how to do anything you need for basics
nano /etc/fstab
i added a line telling me what the drive is then the drive
#proxmox mirror 1tb ext4 /cache
UUID=F6F60A74-6D67-C141-A75F-3F86619FE8D9 /cache ext4 rw 0 0