how to smooth this

this is my line of code:

transform.Rotate(Vector3.up * turnSpeed);

This code is attached to my camera, and it makes the camera jittery. How would I add a smoothing effect to this line of code? Im not too JS savvy either

If turnSpeed is just a constant, you must use the frame duration time (Time.deltaTime) to have a constant rotation:

  transform.Rotate(Vector3.up * turnSpeed * Time.deltaTime);

The frame rate vary a lot, specially when there are few objects in scene. In this case, turnSpeed is in degrees per second (maybe 60 works fine).