Camera preview follow ground

Im making a preview camera of a level. Currently the camera goes directly to the end of the level, but i would like it to follow the ground.

My current script

 if (target)
         {
             Vector3 posNoZ = transform.position;
             posNoZ.z = target.transform.position.z;
 
             Vector3 targetDirection = (target.transform.position - posNoZ);
 
             interpVelocity = targetDirection.magnitude * speed;
 
             targetPos = transform.position + (targetDirection.normalized * interpVelocity * Time.deltaTime);
 
             transform.position = Vector3.Lerp(transform.position, targetPos + offset, 0.25f);
 
         }