Mouse drag get angle

I have a gameobject If i drag it to any direction I want to get the angle in update without my mouse button up,
eg If I drag it to left - 180 , else if right 0 , i drag it in any angle it must give the angle accordingly ,

Nothing is comming in my head

basically I have a curvy path I have to drag the car along the path with mouse and car rotate according to the path with polygon collider,I am able to drag the car along the curve but now i have to rotate it according to curve

any help

If I have understood correctly, you need to rotate the car accordingly to the path. You could add an empty gameobject just before the car and use Quaternion.LookRotation to make the car look at it.