Here's how it works:

* The Sun's core is incredibly hot and dense. This intense heat and pressure force hydrogen atoms, the most abundant element in the Sun, to overcome their natural repulsion and fuse together.

* Two hydrogen atoms combine to form a deuterium atom (one proton and one neutron), releasing a positron (a positively charged anti-electron) and a neutrino.

* The deuterium atom then fuses with another hydrogen atom to form a helium-3 atom (two protons and one neutron), releasing a gamma ray photon.

* Finally, two helium-3 atoms fuse to create a helium-4 atom (two protons and two neutrons), releasing two protons (which become hydrogen atoms again).

This entire process releases an immense amount of energy, primarily in the form of light and heat, which is what we experience as sunlight.

In summary, the Sun's energy comes from the fusion of hydrogen atoms into helium atoms, a process that releases a tremendous amount of energy.