I'm in a few
Group for the estate where I live - they put up messages about things such as estate clean ups, dates for when the grass cutting money is due, warnings about attempted break ins of cars with videos of the culprits etc. They also informed the residents about some damage that was done during a bad storm when some trees and a fence blew down. Then they gave us updates about who they had contacted to rectify these issues and when they would be sorted. I have this one muted, so I just check in every now and again.
Local community group I'm a member of - they put up messages about meetings and events and things that might be of interest to the group.
Book club - they put up messages about meetings and details of the title/author of the book we're due to read before the next meeting and occasionally other things of interest to booklovers.
I'm in a few family groups. One for my wider family (20 odd members) and one just for my siblings. In the wider family group, we exchange birthday greetings and occasionally post photos or greetings from our holidays or we embarrass the nieces and nephews by posting photos of them when they were small and then exclaiming about how cute they were.
The siblings group is for when we want to share something amongst ourselves only, like when my Dad was ill. Or maybe something in the news about the street/neighbourhood where we grew up. Or if an old neighbour or friend of the family has died, we post the funeral arrangements and discuss who is going to the funeral. Our nieces and nephews wouldn't have the same interest in these things or know these people.
Assorted work groups (mostly retired colleagues). We meet for lunch from time to time. I'm still working so I tell them all the news and keep them up to date on who is retiring and who has died.
Assorted friendship groups.
Sounds like a lot and I guess it is. But sometimes weeks will go by with no posts.