As you stand on a floor, does the floor exert an upward force against your feet?
Yes, when you are standing on a floor, the floor is exerting a “normal force” against you. It is called a normal force, as a line that is perpendicular to a surface is referred to as a normal line. If you are standing on a level surface, then the normal force being exerted upwards is the opposite of the weight of the object.
To compute this force for a stationary object, you would multiply mass by the gravitational field strength, which is 9.81 Nkg-1 on Earth. If traveling in an elevator, the normal force can be more or less than the weight of an object if the elevator is accelerating or decelerating.