Why did the early Universe contain only hydrogen but now contains a large variety....Watch this thread
So the stars made these heavier elements and ta dah! Here we are
Light elements (H, He, Etc.) fused together under high temp. and pressure to create heavy elements (Fe, etc.)
More specifically, H and He are fused under high pressure inside stars to make slightly heavier elements, like lithium, boron, nitrogen, and the like, and those elements are fused at even higher pressure to make still heavier elements, and those keep fusing to make even heavier elements. Elements heavier than iron are only produced in the massive, short-lived pressures created by supernovae, which also scatter all of the heavy stellar material over great swathes of space, ready to form new solar systems with planets and life.