Why do both the moon and the earth pull on the spaceship the entire time why must you be closer to the moon for the pull of the earth and moon are equal

1). Because every speck of matter in the Universe exerts gravitational force on every other speck of matter. The strength of the force depends on the masses of both specks, and the distance between them.

2). Because the Earth has about 80 times as much mass as the moon has.