Question about rotate objects please help me !!!

how can I rotate a blades indefinidamente? how can I rotate a door 90 degrees in z axis when I been click the door?

I try with this but I dont know how can I use it correctly.

public float smooth = 2.0F;

Quaternion target = Quaternion.Euler(new Vector3(0,90,0));
transform.rotation = Quaternion.Slerp(transform.rotation, target,Time.deltaTime * smooth);

Well I would reccomend you making the door animation to rotate 90 degrees, it would be easier to code when the animation is played than rotating it 90 degrees in code.

Good Luck juliancruz87.