For DC motors:
The stator is used to generate excitation magnetic fields.
There is armature winding in rotor slot. When armature winding is energized, it rotates under excitation.
The rotor rotates to convert electrical energy into mechanical energy
The structure of electrons and rotors is also different for different types of motors, but the same is true: the stator is immobile and produces a magnetic field; The rotor rotates and is forced to rotate in the stator's magnetic field.