how to make a follow script in unity

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class FollowPlayer : MonoBehaviour
{

    public float attackSpeed = 4;
    public float attackDistance;
    public float bufferDistance;
    public GameObject player;

    Transform playerTransform;

    void GetPlayerTransform()
    {
        if (player != null)
        {
            playerTransform = player.transform;
        }
        else
        {
            Debug.Log("Player not specified in Inspector");
        }
    }

    // Start is called before the first frame update
    void Start()
    {
        GetPlayerTransform();
    }

    // Update is called once per frame
    void Update()
    {
        var distance = Vector3.Distance(playerTransform.position, transform.position);
        // Debug.Log("Distance to Player" + distance);
        if (distance <= attackDistance)
        {
            if (distance >= bufferDistance)
            {
                transform.position += transform.forward * attackSpeed * Time.deltaTime;
            }
        }
    }
}

 var target : Transform; //the enemy's target var moveSpeed = 3; //move speed var rotationSpeed = 3; //speed of turning var range : float=10f; var range2 : float=10f; var stop : float=0; var myTransform : Transform; //current transform data of this enemy function Awake() {     myTransform = transform; //cache transform data for easy access/preformance }   function Start() {      target = GameObject.FindWithTag("Player").transform; //target the player   }   function Update () {     //rotate to look at the player     var distance = Vector3.Distance(myTransform.position, target.position);     if (distance<=range2 &&  distance>=range){     myTransform.rotation = Quaternion.Slerp(myTransform.rotation,     Quaternion.LookRotation(target.position - myTransform.position), rotationSpeed*Time.deltaTime);     }         else if(distance<=range && distance>stop){      //move towards the player     myTransform.rotation = Quaternion.Slerp(myTransform.rotation,     Quaternion.LookRotation(target.position - myTransform.position), rotationSpeed*Time.deltaTime);     myTransform.position += myTransform.forward * moveSpeed * Time.deltaTime;     }     else if (distance<=stop) {     myTransform.rotation = Quaternion.Slerp(myTransform.rotation,     Quaternion.LookRotation(target.position - myTransform.position), rotationSpeed*Time.deltaTime);     }        }