That depends on the laws where you are, and may also be affected by specifics of that rifle. In the US, you don't, unless you're purchasing an NFA tax stamped rifle (short barreled rifles, full auto rifles). Laws will vary in other countries.
No
Yes
In MOST of the US, a permit is NOT required to purchase a .22 rifle. IF one is required in your area, it is because elected politicians passed a law that says you need a permit. You would need to ask them why they did that.
No, the permit system only pertains to handguns. To buy an ordinary Title I rifle or shotgun, you simply go to a gun shop, fill out your Form 4473, have the NICS background check phoned in, and pick up your firearm. Now for pistols, you either need to purchase pistol permits from the Sheriff's Office of your county, or have a North Carolina Concealed Carry Permit.
No. Minnesota requires a transfer permit for handguns.
No, you do not need a licence in Florida in order to buy a rifle.
You get and NFA Class III permit and buy a suppressor.
yes
The SKS is not an assault rifle, nor even a BATFE-defined "civilian assault weapon". And no, a permit is not required.
Depends on Texas law.
I would say Vermont, but I'm not 100% sure. I know you don't need a permit to carry a concealed pistol, or to buy or own a pistol, rifle, or shotgun. Per federal law, you have to be 18 to buy a rifle, 21 to buy a pistol, and you have to pass a background check.
No.