Does fire need air or oxygen?

The fire is fueled by oxygen in the air. There is no significant amount of hydrogen gas found in the atmosphere.
Does the question relate to a laboratory experiment involving hydrogen gas? Or is the question a general one? Oxygen is not a fuel, but it is required to support combustion, or rapid oxidation. Hydrogen is combustible and can be used as fuel. If you burn hydrogen, the fire is being fueled by the hydrogen, not the oxygen, but without O2, the hydrogen would not burn.