How do we know that the stars create the elements in our universe?
All stars in the universe, including the Sun, are fuelled by the energy released during fusion. These nuclear furnaces are responsible for forming all the naturally occurring elements.
Star-created elements are spread through the universe when a star's mass is blown into space during its final life stages.
Radioactive rocks on Earth indicate that the Sun and its planets, including Earth, formed from the gas and dust left from the death of an earlier star. Everything on Earth, including our bodies, is recycled material.