A Twelve-Step fellowship group is a very unusual entity. Because there are so few requirements for its existence, because of the lack of top-down organisation by the fellowship as a whole, and because of the radical group conscience system that can pretty much decide anything, don't start a group unless you're willing to let go of it completely!
At least in Great Britain, conventions and conferences, to bear the AA name, must be financially and operationally accountable to the fellowship as a whole through a representative body (Intergroup(s) or Regions(s)). Again, don't volunteer to serve unless you want to serve!
Does that mean everything has to be a group?
No. A friend of mine runs a big convention for AA members in ... a large western city (but not Akron or Cleveland!) ... and he doesn't use the AA name, because he and his friends want to ensure that the format and content is not interfered with by outside forces.
Similarly, some other friends organise and lead lots of workshops and retreats, which don't bear the AA or Al-Anon name, but are attended by AA and Al-Anon members, amongst others.
Around me, in this city, lots of friends hold all sorts of meetings and events for fellowship members, with a variety of structures and purposes.
Some people hold these in their homes or business premises, or on their personal Zoom accounts.
Importantly, though, these are not groups. They're not part of or affiliated with any fellowship, they do not bear any fellowship name, and they are not publicised through official fellowship networks.
This also means that they're not subject to the radical democracy of the group or the custodial oversight of the fellowship as a whole. Many of the principles of the Traditions and the Concepts might be applied, but Tradition II is adopted either not at all or only in part. They can be run pretty much like a group is run, or they might be run using any other imaginable system.
When setting something up, if you want to retain control over time, location, format, content, and procedures, don't set it up as a group. Do what you want, but don't use a fellowship name or otherwise present it as a group. A convention, a conference, a workshop, a retreat, a meeting, a seminar, anything but ... a group.
If you're happy for what you set up to be surrendered to the whole, apply Tradition II, give up the group to the group conscience, or give up the event to the fellowship.