This tag is also the Pyro Emitter tag, except that here the settings have already been optimized for simulating an explosion. While the normal Pyro Emitter tag has the options for simulating flames and smoke enabled by default, the Pyro Fuel tag only generates fuel. This can then be converted to temperature, smoke and pressure during the simulation, resulting in a typical explosion display. You control this conversion via the parameters linked as Pyro Scene via the Pyro Output object. On this page you will find the explanations of these settings, which you can also find, for example, in the Simulation/Pyro settings of the Project Settings or in the explanation of the Simulation Scene object.
Otherwise, all settings of the Pyro Fuel tag are identical to those of the Pyro Emitter tag and are therefore not explained again here.