how to make projectile track and go to specified enemy in unity

using UnityEngine;
using UnityEngine.AI; //using the unity AI system to move the projectile to the enemy using NavMeshAgent


public class missileMovement : MonoBehaviour //name of the script
{

    GameObject enemy; 


    // Start is called before the first frame update
    void Start() //can also be used in Awake()
    {
        enemy = GameObject.Find("BadGuy"); //find the object tagged with a name, in this instance its "BadGuy"

        GetComponent<NavMeshAgent>().SetDestination(enemy.transform.position);  // gets the component of the projectile
      																			//and then setting its destination to follow the position of the enemy
    }
  //you can add anything you want after this, in general this script has to be on the projectile prefab itself.

  void Update()
  {
     GetComponent<NavMeshAgent>().SetDestination(enemy.transform.position);  // gets the component of the projectile
      																			//and then setting its destination to follow the position of the enemy
    
  }
  
  
}