BuddyPress.org

You should make it a plugin, then add this to the plugin and activate. If you’d like to see a working implementation then check out these plugins:

https://wordpress.org/extend/plugins/buddypress-group-twitter

https://wordpress.org/extend/plugins/bp-groupblog

https://wordpress.org/extend/plugins/external-group-blogs

You should be saving extra group information as groupmeta:

bp_groups_update_groupmeta( $group_id, 'name', $value );