Install the 10TB disk in addition to the three 3TB disks you already have. You will need to work out how to do that. If that isn't possible, even using a USB enclosure, ask what to do before you even start.
Assign a drive letter higher up in the alphabet to that drive. I suggest M:. Google how to do that.
Read this:
https://wiki.jriver.com/index.php/Rename,_Move,_and_Copy_FilesRead it carefully, three times.
Use it to move you music from the 3TB drives to the 10TB drive.
Start by testing with just one or two Albums. Make sure you understand how it works. How you use it depends greatly on how you have set up your Library, whether you use consistent paths to files on each 3TB disk, and thererfore whether you can just move all files from E:, G:, and H: to M: without changing paths. If that is the case, all you need to use is the Find & Replace feature at the bottom of the RM&CF function.
If in doubt, ask first.
Also, there are lots of threads about moving files to new disks. Search the forum.