Does the train go under ground when goin to Disneyland from effil tower?

There is no train that goes directly from the Eiffel Tower to Disneyland. To travel from the Eiffel Tower to Disneyland, you can take the RER A train from Charles de Gaulle - Étoile station to Marne-la-Vallée - Chessy station. The train does not go underground for the entire journey.