in the form of photons
It reaches earth as an electromagnetic wave.
The energy that reaches the Earth from the sun is known as sunlight.
absorbed by earth's core
The majority of the sun's energy is absorbed by the Earth's atmosphere before it reaches the surface.
The Sun's energy is given out mainly as "electromagnetic radiation". Light is a form of electromagnetic radiation. Heat is the main form the Sun's energy has when it reaches Earth, particularly the Earth's surface.
The sun's energy reaches the Earth as solar radiation in the form of electromagnetic waves, primarily in the form of visible light and infrared radiation.
The Sun
The amount of the sun's energy that reaches Earth at a given time and place depends on factors such as the angle of incidence, atmospheric conditions, and geographic location. On average, about 1,366 watts per square meter of solar energy reaches the top of Earth's atmosphere, but not all of this energy reaches the surface due to absorption and scattering.
Energy from the sun travels to the earth's surface is brought here by electromagnetic radiation. Once the radiation reaches the planet, most of it is converted to heat.
Of the Sun's energy reaching Earth's atmosphere, just under 60% reaches the Earth's surface. Only a small fraction of the Sun's energy reaches Earth, of course. In fact it's only about 0.000000045 percent. So, the answer to the question is: about 0.000000025 percent.
It is done by radiation.
Solar radiation.