Come to a meeting. There is no obligation, no cost to visit, and no need to call ahead, though it helps if you do.
Scouts BSA is for youth who are 11 years old, or who have completed 5th grade, or who have earned the Arrow of Light award, through age 17. Most scouts join Troop 101 in 6th grade, either crossing over from a Cub Scout pack or joining directly with no scouting experience at all. Both are completely normal, and first-year scouts are grouped together so nobody is behind.
Troop 101 is a boys' troop. Scouting America also charters girls' troops in the Atlanta area; the Atlanta Area Council can help you find one, or search on BeAScout.
Prospective scouts and their families are welcome at any troop meeting, for as many weeks as it takes to decide. Outings and campouts are for registered scouts, so once your scout joins, they can head straight out on the next one.
Troop 101 is entirely volunteer led. Every family is asked to consider how they can contribute, whether that is camping with the scouts as a trained assistant scoutmaster or handling a committee role from home. See parent involvement for what is open right now.
A troop meeting opens with the scouts, not the adults. Patrols gather, the senior patrol leader runs the agenda, there is skill instruction toward rank requirements, usually a game, and planning for the next outing. Parents are welcome to stay and watch. A few meetings a year are Courts of Honor, where scouts receive the ranks and merit badges they have earned, and parents are expected to attend.
Reach out to Scoutmaster Greg Hebeler at ghebeler@wsp.com or 770-329-2877, or Committee Chair Corissa Wood at corissa.castlewood@gmail.com. See the full leadership list.