What is larger the force the earth exerts on us or the force you exert on the earth?

A non-scientist's initial stab at this: If you are talking about gravity, they are equivalent. I don't see how they can be anything BUT equal. Gravity is an attractive force among two bodies. Every particle of my body attracts every particle of the earth. It wouldn't be stated any differently from the earth's point of view. [Actually, there is a flaw in the way you are framing the question, as the 2 "forces" you refer to can never be divided and studied independently]. The earth has much more inertia, so I move toward the earth.

The attractive force among the earth and moon is much greater than the attractive force among the earth and me. If I were in the moon's orbital path (but nowhere close to the moon) and travelling at the similar velocity as the moon, I'd fly off into space, or maybe enter a wildly eccentric orbit that would eventually bring me crashing into the earth.