The one important thing that neither of the above answers mentions is the great debate over how long ago the Paleo-Indians came to be in the Americas.
The usual answer has been that the Paleo-Indians came via the land bridge around 15,000 years ago. This is known as the Clovis First theory.
This has been challenged in the last decade or so by those who believe that Paleo-Indians came by sea, following the coast in small boats. This school of thought believes the Paleo-Indians got to the Americas significantly sooner, reaching as far south as Chile before the Clovis people got to the Southern US.
The Paleo Indians who first populated the North American continent were wanderers. They presumably crossed somewhere between the land that formed between Alaska and Siberia. Obviously, they kept traveling and settled in multiple regions including South America and possibly the Virginias. Its possible that their journeys were motivated by the hunting of animal herds for food. Evidence of their civilization, so to speak, is often found near lakes and other bodies of water where animals might stop to feed and water. Little is known about these people other than foods that might have been important in their diets based upon artifacts found at excavation sites.
History by definition is a written record or failing that at least a verbal account of the passage of events. In the case of the Paleo-Indians we have neither.
Currently there is much discussion of the apparent discrepancies in the Bering landbridge model. For example why are the oldest sites often found farther south or how do you explain technologies like the folsom point complex?
In addition the presence of anomalies like Kennewick man and certain unexplained DNA features make the answer more complex.
One thing which must be remembered is that if the arrival occurred during the Ice Age there was a significant amount of coastline that would have been exposed allowing for movement there producing sites which are now underwater.
Paleo (means ancient) Indians are considered to be the oldest known people to occupy the Americas. They were commonly found in the southwest and New Mexico in America. They were the longest running culture in America and existed for a period of around 30, ooo years. There has been limited evidence of their existence. They were a nomadic tribe that traveled from one region to another to cope with seasonal changes. They traveled in groups of about two dozen people and brought their belongings on their backs. They did not use any mode of support as they traveled by foot. As time passed they migrated around other areas of the Americas. Clothing consisted of things from nature such as plant fibers and animal skins.
To obtain food they gathered and hunted plants and animals. Their techniques were simple and weaponry was limited. They made simple stone and wood tools that they used for grinding seeds and cutting meats. They used flint making skills and chipped off stone and bones to make useful items. Most of the relics from their society have been found by large bodies of water. Spear points were used for big game hunting but they mostly relied on small or weak animals. Other hunting techniques include forming in groups and chasing an animal off of a cliff so that it would become injured or die. They most likely hunted mastodons in the same manner that the Plains Indians hunted bison.
For thousands of years Earth’s land was covered and locked together by ice during The Ice Age. Animals and humans are believed to have crossed the Beraing Straight, Beringia. The Paleo Indians were nomadic and wander through into the Americas.