Use of Free Form field in Edit Event Notification Rules and Templates Set

Summary:

Hello,

A "Free-Form" message template would allow the sender to write a custom message tailored to the specific needs of the recipient or the situation, rather than using a standard, pre-written message. But I want that where we can write a custom message and when. Do we have any oracle docs or whitepaper related to the Free-Form message template in Edit Event Notification Rules and Templates Set in Subscription Management?

Content (please ensure you mask any confidential information):

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):