Facebook how to send messages to group members?

Question

Facebook

I can’t figure out the face book in any way, there is too much information in https://developers.facebook.com/
There is a group, you need to periodically send messages to participants
So far I see a painful path, write the bot myself and send it out, but this will mainly be used by people far from programming people, so it is desirable to find solutions in 1-2 clicks
Are there any free solutions? or still have to drive a server