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No.
You need to tell us more about the "gun license" and for what area. There are many different gun licenses.
Whether or not you can have a gun license at 20 years old depends on which US state you live in and the type of gun as the laws vary somewhat.
No.
That depends on if your state requires a license or not. Most do not.
With parental permission a license could be issued.
Old enough to spell license.
It depends on where you are and what you mean by gun license. If you are in the U.S. and you mean a permit to carry a gun, check the related link for information.
yes you have to have at any age
Yes. If your valid license is valid in KY, then your suspended license is suspended in KY, too.
you can be 10 but you need a hunters license
10 maybe