The Earth is the only known object (planet or moon) in the solar system that harbours life. It is the planet we live on, it provides for all our needs, water, food and oxygen. For the last couple of billion years, it has support life, although for most of that time, it has been microbaterial.
In fact, the Earth is the only known location in the entire galaxy and universe that supports life. It is just the right distance from the Sun to be the right temperature, not too hot and not too cold for life. The zone which is the right temperature is known as the Goldilocks Zone, named after the fairy tale. If you expand the parameters of the search for life to the Multiverse should that exist then life would exist on some Earths and not exists on other.
It is divided into seven continents which are Africa, Asia, Europe, North America, South America and Oceania. Each of those continents are split into numerous countries, each with their own government and in some case, their own language.
70% of the Earth is covered in water with the other 30% is land. Of the water, only 2.5 percent of water is drinkable, the other is salty. National Geographic
The Earths human population is estimated at being about 7.3 billion people. It is increasing every year as we live longer and are better able to fight off disease. It is believed that by 2100, the worlds population will be 11 billion. Some countries populations are naturally slowing down but others are increasing relentlessly. There might well be a tipping point but when that is, no one knows but it won't be in the short term. The tipping point will probably come about when resources are used up and we can't progress further. BBC