Back then People from America benefited from Mercantilism which is the beliefs in the benefits of profitable trading; commercialism. This can be translated as slavery where they bought and sold slaves to people.
Slaves were sold
In the 17-1800's They had a Triangular Trade. It was between the Americas, England, and Africa. They would trade lumber, metal, Alcohol, and ect... People from the Americas would kidnap people from Africa as slaves and bring them back the America and sell them like property.
Where slaves lived
Slaves were tightly packed into ships and were malnourished. Some even died on the ship from starvation. Some slaves would try to commit suicide by jumping off the ship. That's why they were chained together to stop slaves from doing that. They were only offered one hour of sunlight a day.
Plantations and Farms
It does not sound good but back then you were expected to own slaves. After sailing the sea slaves were bought and sold into the economy as "property".
Slaves were kept in poorly conditioned houses and shacks. With not enough room to hold everyone. If a slave has a child the child is takin away and sold to the slave market.
Women slaves mostly did house work and maid service. The men slaves mostly did the hard labor work like farming and building.