Fuel
Falcon 9 and Falcon Heavy rocket Merlin engines use densified Rocket Propellent 1 (RP1) as a fuel, burnt with densified liquid oxygen (LOX). RP-1 is a highly refined form of kerosene(also know as paraffin).
Starship's Raptor engines use Methalox (Liquified Methane and Oxygen)
How Does SpaceX Get Their Rocket Fuel?