Go out and find an old Colt Woodsman age unimportant, I like my prewar series 1 The grips are not overly large...it points naturally and will outlast the entire family because it is so well made. If not a newer Browning Buckmark or similar will do .
I also found a revolver for smaller hands.... High Standard Sentinel. I have an R-107 with a 4" barrel It is a 9 shot with a swing out cylinder single action trigger is OK double action not so much. It is NOT a Diamondback or a Smith k-22 by any means but it is an inexpensive start.
I like the idea of loading single rounds until the new shooter gets comfortable shooting. We want to create shooters NOT BLASTERS.
For rifles I like magazine fed Bolt Action that can be loaded single shot and later fed from the magazine...again slow aimed fire. Another rifle that is great for teaching is a Savage 6 or Stevens Springfield 87 tube fed semi auto. Use it as a single shot later manually cycle after each shot and eventually permit the full semi-auto....again building basic skills before shooting rapid fire.
All of the above are .22 rimfire feed them good quality ammo and you will get good results