A jet engine keeps the aircraft moving forward using a very simple and complex principle. For instance
What happens when you deflect a balloon? As the pressurized air gushes out, the ballon moves in an opposite direction. ( Newton's third law of motion) just as the air produced by the balloon, makes the balloon move in an opposite direction, so as jet engines works.
The reaction force produced by the high speed jet on the tail of a jet engine makes the aircraft move forward the higher the speed of the vjet. The greater the thrust force. Such high speed exhaust is attained or achieved by a technical combination of techniques.
For instance.. If you can heat the incoming air to a high temperature, it will expand tremendously and will create a high speed velocity vjet, to achieve this purpose a combustion chamber is used
Effective combustion requires air to be in a high temperature and pressure, to bring the air in this condition a set of compressors are used.
*Rotor blades
*stator blades

The rotating blades of the compressors adds energy to the fuel & its temperature and pressure rises to a level suitable to sustain combustion
The compressor receives the energy for the rotation from a turbine which is placed right after the combustion chamber, the compressor and turbine are attached in thesame shaft. The high fuel energy that leaves the chamber mqkes the turbine blades turn,. The synchronized operation of the compressor , combustion chamber and the turbine makes the aircraft move forward..