The life cycle of the sun is called as solar cycle and is the phase of solar development. There are about seven-stage in its life cycle. Starting with the birth of the sun that is found in the solar nebula theory took place about 4.56 billion years.
The sun starts to enter the T Tauri stage, followed by the main sequence stage where the sun is currently in. After this stage that is when the sun runs out of hydrogen from its core.
It will produce violent helium flashes and will shrink its size. When this happens it will reach the tip of the red giant stage. Later on, the naked core will form into a white dwarf.
