Yes.
CO2 pellet guns work by using CO2 for rapid fire, with CO2 the gun does not need to be pumped or recorked after every fire. You can also find spring loaded pellet guns.
Air rifles use compressed air or C02 to propel the BB or pellet. They do not use gunpowder. Their is no bullet shell and bullet just the BB or pellet.
It can be either a BB gun or pellet gun. The slide, on top, blows back and reloads the next shot when you fire the pistol.
You can, but, the question is should you and does it violate any local laws.
Air Soft guns are not designed to fire Pellets. The shape is just wrong but there are steel BB in the 6mm size avalable. But because they are heaver than plastic they fire or travel slower. If the Air Soft gun is not designed to use them they may actually ruin or break the air gun.
It depends on the model and the caliber of the Pellet gun.
Any air gun or rifle that uses a .177 Caliber pellet can use the Gamo .177 Red Fire Pellet. No matter who makes the air gun. The Caliber .177 is universal to all .177 caliber pellet guns or rifles.
I think you mean pellet gun. That is a gun that fires a small lead pellet but does not use gun powder. It uses compressed air or compressed gasses to push the pellet.
While many pellet guns are configured to be able to fire regular BB's, most BB guns cannot fire standard BB caliber pellets. To fire a pellet, the BB gun would have to be a breech loaded or break-barrel loaded design, and the pellets would have to be loaded single-shot.
A pellet gun is not adequate for protection, and will get you arrested.
Any pellet gun should be handled like a real firearm. Yes you can be killed with a pellet gun under the right circumstances.