A point is an exact location. It has no length, width, or height. It has no area or volume. It has no mass, shape, or other physical properties.
As a model ...
-- you could use the period at the end of a sentence printed on paper. It looks like this ==> ·
-- You could use the point of a very sharp pencil.
-- You could use the tiny dot that the point of a very sharp pencil makes on paper.
-- You could use the point of a pin.
-- You could use the tiny hole that the point of a pin makes in a sheet of paper.
These are all bigger than a real point. They all have a little bit of size, length, width, height, and you can see them. But they get the idea across. (They 'make the point'.)