If earth had no atmosphere, would a falling object ever reach termional velocity?

No.  What most people call 'terminal velocity' is the speed of the falling
object when the downward force of gravity is equal to the upward force
of air resistance.  At that speed, the vertical forces on the object are
balanced, so it stops accelerating, and falls at a constant speed.

If there were no atmosphere, there would be no upward force due to
air resistance.  The falling object would continue to accelerate all the
way down until it went 'splat'.

This is exactly the situation for meteoroids or asteroids falling onto the Moon.