type B
That is a B extinguisher, Used for burning liquids, such as gasoline, diesel fuel, paint, grease, etc.
with a fire extinguisher
It will put out burning fluids.
You Don't!
The fire extinguisher contents are designed to interact with the fuel/air boundary, so you need to aim at where the fuel is burning, that is, "at the base of the flames."
Burning liquids such as gasoline, kerosene, paint, acetone, and so on.
Sodium chloride
As you say, its oil primarily "B" category fire extinguishers should be employed...
Carbon dioxide, or foam, or dry powder. At no time should a soda water extinguisher be used, as the water will cause the burning gasoline to flare up and spread even further.
Yes, a fire extinguisher works on a grease fire. What you have to avoid with grease fires is throwing water on them, because the burning grease will just float on the water and will be splashed around as the water heats and vaporizes, spreading the fire, rather than being put out. But the carbon dioxide based fire extinguisher doesn't have that problem.
Generally, no, but a fire would.
Like any other fire, a burning candle requires fuel, heat, oxygen and a chemical reaction. If you use a fire extinguisher, it typically removes the heat or oxygen from the process, thus stopping the fire.