How long does it take for a star to form? Have we seen stars form?

Hint: The Stars are the huge celestial bodies that are made up mostly of hydrogen and helium and produce the light and the heat from the churning nuclear forges inside the cores.

Complete answer:
The formation of the star process will take around a million years from the time when the initial gas cloud starts to collapse till the star is formed and shines like a sun. The material that is leftover from the birth of the star is used for the formation of planets and also the other objects that orbit the central star.
When the atoms of the light elements are squeezed under the pressure for the nuclei to undergo the fusion process, then a star is born. During this process, the force of gravity compresses the atoms in the interstellar gas till the fusion reactions start, and thus we can say that all the stars are the result of the balance of the forces.
Scientists have predicted in detail the birth of a massive star within a dark cloud core of about 10,000 light-years from the Earth and this cloud is estimated to form at least one star which is 100 times more massive than the Sun and also brighter up to a million times than the star.
It takes millions of years to die for the stars. Whenever the star begins to run out of fuel, the star’s core shrinks and becomes a white dwarf.

Note: 1. Like human beings, stars also will be born and grow, become old and die.
2. Constellation is the term that is used by astronomers to refer to an area of the sky.