I take it you're not thinking of yourself as one of these 2 or 3 billion
Is it ?.
Some cities are densely packed, but much of the planet is uninhabited. in fact great swathes of land have nobody living there.
Here is a link to the Wikipedia page for the Earth.
Earth - Wikipedia
According to this source, land occupies just over 29% of the Earth’s surface, or 148,940,000 square kilometres. There are 1,000,000 square meters in a square kilometre, so there are 148,940,000,000,000 square meters of land on the surface of the Earth. That’s approximately 150,000 billion square meters of land.
According to this source,
World Population Clock: 7.5 Billion People (2017)
there are approximately 7.5 billion people currently living on earth.
If you divide 150,000 billion square meters by 7.5 billion people, you get about 20,000 square meters per person. You can think of that as a square about 140 meters on a side. That’s enough for a very nice house and a big garden.