Question

How is white dwarf created

Answer 1

it is not created it is a stage of a star which happens in it's life cycle

Answer 2

If a red giant has insufficient mass to generate the core temperatures, around 1 billion K, required to fuse carbon, an inert mass of carbon and oxygen will build up at its center. After such a star sheds its outer layers and forms a planetary nebula, it will leave behind a core, which is the remnant white dwarf.