I herd that if we travel with the speed of light for 7 years , in earth will have past 500 years. But what if we have a point A were the spaceship will start and a point B were the ship will stop. Both points are visible from earth. In the ship travel with the speed of light from point A to B for 7 seconts does that mean that we will see it like he needed 50 seconts? Sounds paradox

You mean if we are watching from earth? In that case we will see the incident happened a little bit later.