Short answers, pulled from the story.
Earth formed approximately 4.5 billion years ago from gas and dust in the early Solar System. The oldest material found in the Solar System dates to 4.5682 billion years ago, and the primordial Earth had assembled by around 4.54 billion years ago.
Water covers 70.8% of Earth's surface, or about 361.8 million square kilometers. Almost all of this is the global ocean; only 2.5% of Earth's total water is fresh water, and most of that is locked in glaciers and ice caps.
The most widely accepted theory is the giant-impact hypothesis, which holds that a Mars-sized object called Theia collided with the early Earth. Material ejected by the impact coalesced into the Moon, which explains the Moon's relative lack of iron and its composition nearly identical to Earth's crust.
Earth's axial tilt of approximately 23.44 degrees causes the seasons. As Earth orbits the Sun, different hemispheres receive more direct sunlight at different times of year, producing summer and winter. The Northern Hemisphere's summer solstice currently falls around the 21st of June.
The Great Oxidation Event occurred roughly two billion years ago, when oxygen released by photosynthetic life accumulated in the atmosphere. This transformation enabled aerobic organisms to proliferate and led to the formation of the ozone layer, which shields Earth's surface from ultraviolet radiation.
Earth's long-term fate is tied to the Sun. Rising solar luminosity will make the oceans evaporate within an estimated 1.6 to 3 billion years. When the Sun becomes a red giant in about 5 billion years, Earth may be vaporized inside the Sun's expanding atmosphere, or may survive in a wider orbit depending on tidal effects.