What's inside a star?

A star’s energy is created in its core, and is radiated into space from its surface. In between, the energy is transported by various means. Gas constantly leaks away from its surface into space as stellar wind.

Deep inside the Sun, energy from the core is transported by radiation (the radiative zone). In the outer layers, the convective motion of gas transports heat to the glowing surface; this is known as the convection zone. Other stars have different internal structures. In red dwarfs and red giants, the convection zone is much thicker, relatively speaking; in blue giants the radiative zone lies outside the convection zone. Energetic flares, dark sunspots, subsurface gas flows and solar wind are all governed by ever-changing magnetic fields.

What would you see if you could look inside the Sun? Very hot gas in the centre, and a layer of "boiling" gas closer to the surface. Magnetic fields tell the gas particles how to move. They also create sunspots.