There isn't a readily accessible, easily-identifiable "fuel cut-off switch" like you might find on some other vehicles in a 1998 Honda Legend. Honda doesn't typically include such a switch as standard equipment. To stop fuel flow, you would need to disconnect the fuel pump relay or the fuel pump itself. However, this is a more involved process that requires some mechanical knowledge and isn't something you should attempt unless you are familiar with car mechanics.
Do not attempt to disable the fuel system unless you are experienced with car repair. Incorrectly disconnecting components can damage the fuel system and is potentially dangerous due to the flammable nature of gasoline.
If you need to disable the fuel system for safety or other reasons, it's best to consult a qualified mechanic.
