For the British, the home is private place in which he or she goes to hide away from the troubles of life. It is very seldom that one would be invited to a British person's home. It is rude to knock on a person's door if you are not invited. If you are invited, don't ask to see more than the downstairs that your British host invites you into. Never ask how much the house or any of the items in it cost.
To the American, most of them want their home to be a place where they can entertain (款待) and share their lives with their friends. They may be delighted to give you a full tour of their houses. They may also be pleased when you show your interest and pleasure in their houses.
Both British and American people will engage in quite a bit of chat and a drink or two before the meal is served. After the first mouthful, you should say how delicious the food is and ask something about it. Remember, never eat with your mouth open and make very little noise while eating. It would be nice of you to help your host in any way. Maybe offer to pour some drinks or clear up after the meal.