You can edit group details to customize your group name, description, image, type and so on.
If you're a group owner or administrator, you can edit details such as the group's name, description, type and so on — the same things you entered when you created the group. These details help people find your group and know exactly what your group is up to. Think of the group's details as a book cover that potential members can glance at to decide whether the group is somehting they need follow to get the latest news.