You don't need an ID of any sort to conceal carry a gun in AZ, but you need one for an app?
Only if the bill is voted on, approved and signed into law, which I would bet top dollar will never happen.
Can children buy guns in AZ? Look, I don't have an opinion here one way or the other, this almost certainly won't pass, but please at least try to argue in good faith.
The 2nd amendment is the only constitutionally-guaranteed right these days. And that too only if you have the correct political views.