In addition to MrDeplorableUSA’s excellent comments I’d add that depending on how the drive was formatted you may need to change the ownership so that you can use as a standard user.
I typically run:
Give ownership to the logged in user (you)
sudo chown $USER [the new drive address (/dev/sdb)]
Add the drive to your group
sudo chgrp $USER [the new drive address (/dev/sdb)]
There is probably a better command that removes permissions so anyone can read and write to the drive but I don’t have it handy.
I also use lsblk to triple check the drives connected to the machine. “List the block devices and partitions”
lsblk will show the primary drive tree as /dev/sda with the partitions /dev/sda1…2…x
Hope this helps.