Input Axis is Not Setup

Hello. I am working on a flight simulator. I watched a tutorial on making air flight and downloaded an asset used in the video given by the creator. In one of the scripts, it is looking for an axis called, "Yaw." But when trying to run the game I get an error saying Input Axis "Yaw" is not set up. This is thescript, is something wrong? using System.Collections; using System.Collections.Generic; using UnityEditorInternal; using UnityEngine; using UnityEngine.SceneManagement;

 public class AirplaneController : MonoBehaviour
 {
     [SerializeField]
     float rollControlSensitivity = 0.2f;
     [SerializeField]
     float pitchControlSensitivity = 0.2f;
     [SerializeField]
     float yawControlSensitivity = 0.2f;
     [SerializeField]
     float thrustControlSensitivity = 0.01f;
     [SerializeField]
     float flapControlSensitivity = 0.15f;
 
 
     float pitch;
     float yaw;
     float roll;
     float flap;
 
     float thrustPercent;
     bool brake = false;
 
     AircraftPhysics aircraftPhysics;
     Rotator propeller;
 
     private void Start()
     {
         aircraftPhysics = GetComponent<AircraftPhysics>();
         propeller = FindObjectOfType<Rotator>();
         SetThrust(0);
     }
 
     private void Update()
     {
         if (Input.GetKeyDown(KeyCode.R))
         {
             SceneManager.LoadScene(0);
         }
 
         if (Input.GetKey(KeyCode.Space))
         {
             SetThrust(thrustPercent + thrustControlSensitivity);
         }
         propeller.speed = thrustPercent * 1500f;
 
         if (Input.GetKeyDown(KeyCode.LeftShift))
         {
             thrustControlSensitivity *= -1;
             flapControlSensitivity *= -1;
         }
 
         if (Input.GetKeyDown(KeyCode.B))
         {
             brake = !brake;
         }
 
         if (Input.GetKeyDown(KeyCode.LeftControl))
         {
             flap += flapControlSensitivity;
             //clamp
             flap = Mathf.Clamp(flap, 0f, Mathf.Deg2Rad * 40);
         }
 
         pitch = pitchControlSensitivity * Input.GetAxis("Vertical");
         roll = rollControlSensitivity * Input.GetAxis("Horizontal");
         yaw = yawControlSensitivity * Input.GetAxis("Yaw");
     }
 
     private void SetThrust(float percent)
     {
         thrustPercent = Mathf.Clamp01(percent);
     }
 
     private void FixedUpdate()
     {
         aircraftPhysics.SetControlSurfecesAngles(pitch, roll, yaw, flap);
         aircraftPhysics.SetThrustPercent(thrustPercent);
         aircraftPhysics.Brake(brake);
     }
 }