Toward the end of the last ice age, what power source was discovered that humans transition away from a nomadic lifestyle?

Quaternary glaciation is the most recent ice age, starting from 3000 years ago and continuing until today, but several glacial and interglacial periods are recognized, currently living in the ice age in Antarctica, Greenland and the Arctic (Regions covered with ice), but it is also in interglacial limitations, due to the warm climates of the planet, it is also assumed that in conjunction with the ice age that was lived, phenomena that allowed advances in man with respect to its source of energy and its lifestyle that is explained with Prehistory.

In the Palaeolithic, the first human beings who inhabited a 7000 years ago feed on fish and other animals. These human beings moved from one place to another, so they were nomads, lived in caves, cabins and outdoors. It was then that 7 million years ago they discovered more profitable and evolved energy sources. Likewise, they already lived in villages and towns, these humans stopped being nomads and became sedentary in their lifestyles. They also managed to manufacture stone tools and vessels.