I READ FROM A BOOK THAT ALL ELEMENTS EXCEPT HYDROGEN ARE FORMED IN STARS DUE TO NEUCLEAR FUSION.IS THIS TRUE? THEN WHAT ABOUT HYDROGEN?

The Sun is composed primarily of the chemical hydrogen and helium; they account for 74.9% and 23.8% of the mass of the Sun in the photosphere, respectively. All heavier elements, called metals in astronomy, account for less than 2% of the mass. The most abundant metals are oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%).

When other stars are studied spectroscopically it is found that most stars are composed of around 70 percent hydrogen and 28 percent helium by mass, very similar to what we see in the Sun. The fraction of all other elements, the "heavier" elements, is small and varies considerably