Licence requirements are based on the laws WHERE YOU ARE. They vary greatly from one country to another, and one US State to another. And YOU did not tell us where your are. In most of the US, no, a license is not required to purchase a semi-auto AR15. Your spelling of 'licence" may indicate you are not in the US. In Australia, a licence is required to obtain ANY firearm. An AR15 is a Class D firearm, and cannot be owned by the average private citizen.
yes
No.
no
no
yes, you just need a license
Generally, no.
No.
No ... but their may be an age requirement.
It would depend on what state you live in ... but in most states you would not need a license ot own a softair gun ...
You don't need a gun license if you are 25 but if your under 25 you do need a gun license
Yes, most assault rifles are illegal, unless granted special permission and you have acquired a special gun license from the Cayman Islands Gun Club.
You never need a license to have an Airsoft gun.