My own summary is given in the Stellar evolution handout . This is packed with information, all of which you need to know. We won't cover this section in the detail that the text does. There are clouds of gas and dust here and there throughout the universe. Occasionally these clouds collapse to form stars.
Gravity pulls the material together.
Most falls into the center to become the star. Star formation is going on even today. About 10 new stars are born every year in our Milky Way galaxy. The nearby Orion Nebula is a region of active star formation. Protostar Stage Gravitational contraction of an interstellar cloud.