Earth is estimated to have formed about 4.54 billion years ago. Scientists predict that it will remain habitable for about another 1 to 1.7 billion years. After that, it will become too hot to support life as we know it.
The main reason for Earth's eventual demise is the Sun. As the Sun ages, it will become hotter and larger. In about 5 billion years, it will enter the red giant phase, expanding outward until it engulfs Earth.
Even before Earth becomes uninhabitable due to the Sun, it will likely undergo several other dramatic changes. In about 1 billion years, the Sun's luminosity will increase by about 10%, causing Earth's oceans to evaporate.
This will make Earth a barren wasteland, long before it is actually engulfed by the Sun.
Of course, it is also possible that Earth could be destroyed before these events occur. For example, a large asteroid impact could wipe out all life on the planet.
However, based on our current understanding of the universe, it is more likely that Earth will simply become uninhabitable due to the natural processes of stellar evolution.