Why did the first Americans migrate from Asia to Americans?

One of the most common theories is that humans migrated from Asia to America through the Behing Strait between 15,000-40,000 years ago. There is no unanimity among scientists, because no found evidence has been deemed conclusive. They must have crossed on an iced land bridge, that's the longstanding theory called the Bering Land Bridge. Such migrations were motivated by the search for new territory, food and hunting areas.

Because far eastern Siberia was once connected to Alaska