There is a point on the Earth where Polaris, the North Star, is directly overhead. But if you stand in your northern latitudes and see it off at an angle you think, “It’s light years away and the earth is tiny. No matter how far I walk in that direction, I’ll never be underneath it”.
But you can. Let me explain.
In your imagination, draw a straight line. Begin at the center of the Earth then go directly through space to Polaris. That line has to pass through the surface of the Earth. If you walk over to where it comes out, your feet will be straight down and Polaris will be straight up.
This is true of all the stars; but Polaris, because it is above the axis we spin on, is always overhead at the same spot – our North Pole.