the result i want is similar to angry birds but from top view camera and no gravity would be included , or more like Knife Hit game except i want to shoot the projectile either straight , right curve or left curve .
Ok, so you need the path thet the projectile will follow?
Then you can do a “trick”. Generate a new object called something like “path definer”. This object is not the projectile,it does not have mesh, but it moves the same as the projectile will. In this object, add only a Line Renderer: Unity - Manual: Line Renderer component
So it will Draw the path that a projectile will follow.