ParaView has a group of display options labeled Backface Styling where you can think of the “backface” as the “internal” side of a polygon. By default, the backface representation follows the frontface so they look the same.
You can change the representation of the backface (or remove backfacing polygons entirely). Once you do so, you can also change the color of the backward facing polygons.
(See also Colour different sides of a surface different colours .)