Go to a paintball store and pay for them to fill it.
At most Sporting goods, gun, and paintball fields. Some Gas (not just gasoline, but Ike propane) places you can fill your CO2.
if you're asking how to refill the tank you take it to a local paintball shop or sporting goods store, they can fill them
No paintball gun will work without a CO2 tank or other propellant tank. without Co2 there is nothing to push the ball out of the barrel.
You will need an all new regulator.
Where the air tank or co2 tank normally attaches
There is no such thing as a "CA" tank.
You fill your gun with paint in the hopper. the CO2 or nitrogen tank pushes out "air" and forces a paintball through the barrel and at your opponent.
At any local paintball store.
A paintball gun, unlike airsoft or real firearms will have a hopper on top, and will have a co2 tank sticking out of the back.
No, any tank will work.