Looking for some guidance and recommendations on a proper fly rod set-up for my boy.

I've got a 8 y/o that i bought a "Wild Water Fly Fishing 9 Foot, 4-Piece, 5/6 Weight Fly Rod" for off amazon because he wanted to try it. Let's just say the first day he figured it out he caught 14 bass with it and hasn't picked up a bait caster since. Would like to get him something of quality as he is darn good at it and spends 2-4 hours a day fishing, all day if I let him.

I know absolutely nothing about fly rods, weights, tippet, etc. Is there a quality setup out there that would be good for everything from pond fishing to inshore?

Any video/literature recommendations?