The only place on Earthg the sun woulkd go directly overhead and go down perpendicular to the horizon would be if you lived on the Tropic of Cancer or Capricorn and only when that actual part of the Earth was pointing straight at the Sun (I'm thinking Summer Solstice in the two various parts of the world).
Otherwise, the sun will set and rise at an angle to the horizon. It follows a cut off arc across the sky. (Although, in very northern and very southern climes in summer it will follow a circle in the sky because the sun will not set.)
I hope that helps. It's a strange question.