Maglev trains, like the one shown in the picture, use magnet fields to travel up to 600 miles per hour. magnets on the bottom of the train and on the tops of the rails have similar magnetic poles. based on properties of magnets, how do these magnets affect the train?

They cause the levitation of the train.
In fact, magnets with same polarity repel each other. So, the magnets on the tops of the rails repel the magnets on the botton of the train: this repulsive force is strong enough to win the weight of the train, and the train levitates in air. As a consequence, the frictional forces acting on the train are very small compared to the forces experienced by normal trains (that should win the frictional forces of the railway), and therefore this Maglev train can reach a huge speed.