Question

Only a fraction of the energy that reaches the Earth’s orbit from the Sun, reaches the atmosphere of the Earth

Answer 1

It is true that only a fraction of  the energy that reaches the Earth’s orbit from the Sun, reaches the atmosphere of the Earth.

The fraction of the total solar radiant energy reflected back to space from clouds, scattering and reflection from the Earth's surface is called the albedo of the Earth-atmosphere system and is roughly 0.3 for the Earth as a whole.