I heard I could find my relative (member of church) ..How
Perhaps you are referring to "Map Your Ancestors". It's a feature on the Family Tree App - on your phone.
Open the Family Tree app, tap More in the bottom right corner (iOS) or the top left corner (Android), and then tap Map My Ancestors. A map will then show you a 100-mile radius around your current location. Here’s what the icons on the map mean:
Here is a blog article about the feature - https://www.familysearch.org/en/blog/whats-new-map-your-ancestors
What a neat feature!