Congrats on creating a group on OpenSports!
In oder for your group to be discoverable in the Groups Discovery section (the second tab in the main navigation bar), you need to invite your first 10 members.
Players will go to the Groups Tab (second icon from the left, from the main navigation bar). From here, they can scroll through local groups, and/or search for public groups by tapping on the search icon.
When a player finds a group they are interested in, they can tap on it, read the group details, and click the Join button.