Groups are the bedrock of AA (or CA, Al-Anon, etc. for that matter)! They function to help focus on recovery but also to provide a forum for providing service opportunities for us to give back to the community of recovery and futher our sobriety.
Check out this guide for to learn more about service positions in the group (and at the District and Area Level).
https://www.scribd.com/document/447900338/AA-Service-Positions-the-Foundation-Group-04-2016