A simple explanation of what will become of the Earth is here:-

https://en.wikipedia.org/wiki/Future_of_the_Earth

The end?:-

Four billion years from now, the increase in the Earth's surface temperature will cause a runaway greenhouse effect. By that point, most if not all the life on the surface will be extinct. The most probable fate of the planet is absorption by the Sun in about 7.5 billion years, after the star has entered the red giant phase and expanded to cross the planet's current orbit.