What is the parts of the star?

Answer 1

It depends on how massive the star is and what part of its life its at. Most of the time the core is the hottest, but after a star runs out of its current fuel it will start fusing elements in a shell around its core out to the surface or photosphere. While these shells are burning they are the temporary hotspots of the star, while the core gets hotter and hotter.

Answer 2

A star is composed mainly of hydrogen and helium gas, with some trace elements. The core is the region where nuclear fusion reactions take place, generating heat and light. Surrounding the core are layers of gas where energy is transported through convection and radiation, eventually reaching the surface where it is emitted as light and heat.