If you just install a new HDD to your Ubuntu. You posiblly cant use it right away. Here is how you use it.
Open your disks windows find the format partion.
After you are done creating your partitions (most likely it will be just one ext4 data partition, since this is your additional storage drive), you need to permanently mount it.
At this step you already know what names your new partition(-s) have. If not sure, following command will remind you about existing drives and partitions on them:
sudo fdisk -l
This will output something like this (intentionally skipped /dev/sda system drive info):
Disk /dev/sda: 5.5 TiB, 6001175126016 bytes, 11721045168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disklabel type: gpt Disk identifier: 400CBE60-FC0F-03A8-982F-03D0033FEA00
Device Start End Sectors Size Type /dev/sda1 2048 11721039871 11721037824 5.5T Linux filesystem
//or this in other pc Device Boot Start End Sectors Size Id Type /dev/sdb1 2048 976769023 976766976 465,8G 83 Linux
Usually it in the last line
Output states, that your new partition is /dev/sdb1. Now you need to mount it to utilize it's precious space. To achieve this, you need to perform three simple steps:
2.1 Create a mount point
sudo mkdir /hdd
2.2 Edit /etc/fstab
Open /etc/fstab file with root permissions:
sudo nano /etc/fstab
And add following to the end of the file:
/dev/sda1 /hdd ext4 defaults 0 0
2.3 Mount partition
Last step and you're done!
sudo mount /hdd