In fact: Rockets work in space by using a fuel and oxidizer to create a combustion reaction. The fuel and oxidizer are stored in the rocket and do not rely on the oxygen in the atmosphere. The combustion reaction creates high-pressure gases that are released from the rear of the rocket, which propels the rocket forward.
ScienceABC
“You only need two components for a combustion reaction: the fuel and the oxidizer. Most space rockets carry their own fuel and oxidizer with them into space, so they don’t rely on the availability of oxygen out there“
Since fire needs oxygen to burn, how do rockets work in space →
Street Science
“Oxygen is the most common oxidiser on Earth. When fuel is burned, the atoms in that fuel release electrons. An oxidiser accepts those electrons and the chemical reaction makes the fire burn much more intensely. Think of it like fanning the flames of a campfire to make them grow. That chemical reaction is important for rocket fuel because it takes an incredible amount of power to get a ship off the ground and into space.”
Live Science
“Rocket engines operate using combustion. Since all forms of combustion need oxygen, rockets carry an oxidizer like liquid oxygen up to space with them. That means they don’t have to rely on surrounding air like a car engine does.”
MIT
“The fuel of a liquid-propellant rocket is usually kerosene or liquid hydrogen; the oxidizer is usually liquid oxygen. They are combined inside a cavity called the combustion chamber. Here the propellants burn and build up high temperatures and pressures, and the expanding gas escapes through the nozzle at the lower end.”
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