When objects explode, the pieces usually travel outwards in all directions. Bu tif an object is designedso that it does not break up, and everything that comes out of it goes in one direction, then you have a rocket.
A rocket works but pushing burning hot gases out of the base, this then pushes the rocket in the opposite direction.
Rockets carry with them everything they need to make the burning gases they push against. This means that they can work in space as well as in air.
Jet engines use the same basic idea as rockets. Air is drawn into the engine and pushed out at the back. The other force of the pair pushes the engine forward. Jet engines need to draw air in, so they cannot work in space.
How does a Car get Moving?
To make a car move, the engine has to make the wheels turn. The wheels are pushing backwards on the road and the car is pushing forward on the road and this make the car move.
It is similar with walking, you push backward n the ground with your feet and the ground pushes forward on your feet causing you to move.
When you walk on a slippy surface it is hard for you to push back on it and so it is hard for the surface to push back on you, this is why it is hard to walk on slippy surfaces.