Without more information, the answer could be yes, no or maybe. How old are you? What are you planning to do with the BP? Where are you?
No.
18 but if you are under 18 but over 12 you can have a minor's license where you can't purchase a gun but you can use one and buy ammunition.
Nope. Pellet guns are fairly safe to use.
With a license, yes. Without a license, no.
The agency that issues the license will tell you.
With a license, yes. Without a license, no.
Yes, you do not need a gun license to buy a clip, but you may need one to legally possess and use it depending on local laws.
It depends. Some, but only a few, states in the U.S. require a license to purchase a gun. A gun permit normally refers to a permit allowing you to carry the gun on your person in public. Some people use the terms interchangeably, but each state calls the gun permit something different. In Tennessee, it is called a "Handgun Carry Permit." In Florida, it is a "Weapons Permit."
With a license, yes. Without a license, no.
Making guns is not illegal. In US, anyone can make a gun that is not fully automatic for their own use without any sort of license, permit, or registration. Making guns commercially (for sale to other people) is also legal, but you have to get a license and pay a tax. Outside of US making guns is also legal in many places, provided you get an appropriate license.
Many questions about copyright boil down to "can I do this?"is this protected?who controls it?can we use it without a license?how much can we use without a license?who do we get a license from?how long will it last, how much will it cost, and is it worth it?
It depends on where you are and possibly who you are. In general, though, it is probably legal in most if not all locations in the US to possess (though possibly not to use, without the proper license) a tattoo gun.