Okay kiddo, so you know how some people want to dedicate their whole lives to serving God, right? Well, the Congregation for Institutes of Consecrated Life and Societies of Apostolic Life is like the grown-up group that helps to organize and oversee these special people, who we call consecrated men and women or apostolic individuals.
This group makes sure that these people are doing what they're supposed to be doing: following the rules and guidelines that they promised to follow when they dedicated their lives to God. They also help to create new groups of these consecrated and apostolic people, and help to make sure that they have the resources they need to keep serving God in the best way possible.
Think of it like a big family that helps make sure all of its members are doing well and following the rules. This group helps these special people do their very best work for God, and helps to make sure that their work will continue for generations to come.