CSHARP

euler to quaternion

//Writes the rotation of these in Quaternion
Debug.Log(Quaternion.Euler(new Vector3(0, 10, 20)));

quaternion to euler

//Writes the rotation of the gameObject in euler angles
Debug.Log(transform.eulerAngles);

//Writes the rotation of the gameObject's x value in euler angles
Debug.Log(transform.eulerAngles.x);