How to encrypt Full Disk on Multiple Disk Installation

Hi,

I am trying to install Ubuntu on both of my Hard Drives of my Laptop .
I would like my /home on HDD B, and root/BOOT/SWAP on HDD A.
I would also like both my /root, /swap and /home to be encrypted so that both my OS and Files and encrypted.

So the partitions should look something like:

A:
- /root (encrypted)
- /swap (encrypted)
- /boot

B:
- /home (encrypted)

I can create the partitions fine, but don't understand how the encryption bit works.

Thank you very much in advance!