Answer: by crossing the Bering Strait.
Step-by-step explanation:
Migration is the process by which human beings move from one territory to another, usually driven by the search for better living conditions.
The first humans to migrate to the American continent did so during the ice age through the Bering Strait; Due to the glaciation, there was an ice bridge over the ocean that connected the American continent with the Asian continent. It is believed that they did so by following herds of animals that they hunted.
I hope this information can help you.