CO2 tanks are easy. now that paintball is getting really popular you are seeing more places that fill tanks. any paintball shop (of course) will fill it and even places like Dick's. Just try anywhere that sells paintball gear.
At most Sporting goods, gun, and paintball fields. Some Gas (not just gasoline, but Ike propane) places you can fill your CO2.
Remotes allow to mount your air or co2 tank of your paintball gun.
No, paintball co2 is much higher pressure.
Co2 (or sometimes High Pressure air) is what operates the paintball gun. The compressed Co2 is what physically moves the paintball out of the barrel as it expands. It is also what resets the mechanical parts on semi-automatic paintball guns. Without Co2 you cannot operate a paintball gun.
Most places allow you to rent a gun.
A paintball gun needs CO2 (or HPA) to fire at all.
No there is no licence required to purchase/operate a paintball marker. In order to play you must be at least ten (at most places) and 18 to purchase a marker, balls, or CO2.
CO2, stored in the tank is highly pressurized. The paintball being shot is caused by it being pushed out by the rapidly expanding gas. CO2 also cycles and reloads the next paintball.
There are a few places that will fill your CO2. Local paintball stores will, as well as their fields (if they have one). Places that refill scuba tanks will as well. Finally even some hunting stores will.
A Co2 gun can go up to 300 fps. Sling shoots only get a paintball up to 240.
Go to a paintball store and pay for them to fill it.