What is a star's 3rd source of fuel for most star sizes?

Star can be called huge celestial bodies. These stars are made up of mostly by hydrogen and helium.

Explanation:

The stars are made up of helium and hydrogen. These gases produce the light and heat from the churning forces of these gases inside their core.

To except the sun, the dots we see in the sky are all light-year from the earth. These are called the building blocks of the galaxies in the sky.

There are several billions of galaxies in the universe. But there is not an exact estimate but around three hundred billion galaxies are present.

Mostly helium and hydrogen are the fuel source of these most star sizes.