Yes. But not in public.
Yes, provided they have appropriate supervision.
In the U.S. 18 for rifles and shotguns, 21 for handguns.
No sn data in the public domain
The state of Illinois does not issue carry permits, so it's illegal at any age to carry a gun in Illinois, assuming you mean out in public with a gun permit.
Anne Hold That Gun
Select the gun and hold a or press a for shooting
Depends on the gun. I have some that hold 1, some that hold 30.
Gun Dealers and gunsmiths
Which gun?
Hold the gun with the barrel pointed in the air and with your finger off of the trigger. It is best to hold it in a holster.
Depends on the handgun. There is no one number. I have some that hold 1, some hold 15.