As far as I can tell, but I'm no expert, never used Calibre on anything except my PC, but I have manipulated entire Calibre Libraries, and the process is the same.
CC's entire reason for existing appears to be to wirelessly access the internal contents, of an
existing Library stored on another device in the cloud (including your PC, which is "in the cloud", but only when on your local network).
You want to transfer an entire library to your Tablet, so you can access it directly when that local network is unavailable.
Transferring an entire Library, is easy enough to do Manually, assuming you have some means of transferring files/folders from your PC to the Tablet.
USB works just fine for android phones, so should for your Tablet, even wireless should work, and already be set up if you're using CC to access the library.
I strongly recommend using USB, as it removes unnecessary networking complications from the entire process
See this Calibre FAQ on transferring your Library folder to another Computer, and accessing it with Calibre installed on that computer.
How do I move my calibre data from one computer to another?
It's pretty straight forward wired, once you set your Tablet to permit USB connections, your PC should see the entire file folder structure like it would for any drive connected via USB.
Older Android devices have a system section under settings, but for newer ones it only pops up as a notification after a USB connection is made.
Once the USB is plugged into your PC, and Tablet you should get a notification, about System USB connections, click on it, to see further options.
You need set it to allow file transfer, and if offered the choice, give the PC control, as it's always easier to do file management on the PC.