When adding a new disk to the system (depending on the capacity of the drive being added) you may have a few possibilities once you have it physically installed.
In most instances, you will need to go into Disk management and initialize the disk and then format it before you can begin writing data to it. Once that is done then drag and drop or copy paste will put data on the drive. As you install new programs you can also have the option of install to the new drive as well. Just be aware that doing so means that if you remove that drive, your programs will stop working (since they are on the drive and not in the system anymore).
I may have missed some points but ask away if you have any other questions. Hope that helps.