What part of the Saturn system reached the Moon's surface?

Answer 1

The lunar excursion module. Which was located inside the upper part of the third stage of the Saturn system, adjacent to the command module.

After leaving earth orbit, on the way to the moon, the command module turned around, docked with the lunar module, and extracted it from the third stage. The combined unit turned again and faced the moon. The third stage drifted into space. The excursion module then separated from the command module for its trip to the moon's surface. The command module remained in lunar orbit waiting to receive the astronauts from the returning module.