There is no specfic age. Just make sure that if it is a child, he/she can handle the gun as if it was real. You must also be 18 to PURCHASE them, not to use them.
no
yes you can but be careful.
Your parents will decide.
21
If its a BB Gun, Then Yes.
It all depends on the law where you live.
18 to purchase
You need to take this question up with the child's parents.
You must be 18 Years old to purchase one
18 years old
Depends on your skills, size and parents.
No