Encryption and EBYTE 220 library

Hi I was trying to understand how the library's encryption system works. In the topic, "Basic configuration option", it says that it would be possible to configure encryption with "CRYPT Encryption to avoid interception 07H". (link) In the E220 module, is there signal encryption (internal to the LLCC68 module) or just the message (Ebyte220 library)? Do I need to configure any settings to enable message encryption? Can I change library encryption keys? How?