Inform yourself about the Kepler´s laws. If the sun moves while the planets orbits it, then the planets can not be orbits the sun on ellipses.
However, Kepler's laws only work with ellipses.
The planetary orbits are, in fact, spirals. This proves that the heliocentric modell is wrong, because it is based on Kepler's laws. If you are comparing this with a train or an elevator, remember that they have a physically fixed reference plane (the floor), Where is the referential plane in the solar system? Just think about this and all others?
The heliocentric model which taught in schools and universities is wrong. The sun does not stand still in the center.