Enemy chases any object with player tag (no navmesh)

I can't use navmesh agent because my game is an infinite runner, im stuck on how to find gameobjects with tag

 

came up with this script:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class CHASE : MonoBehaviour {
6.  
7.     private Transform target;
8.     public float speed = 1.0f;
9.  
10.     private void Start()
11.     {
12.         target = GameObject.FindWithTag("Player").transform;
13.  
14.     }
15.  
16.     // Update is called once per frame
17.     void Update()
18.     {
19.         float step = speed * Time.deltaTime;
20.         transform.LookAt(target);
21.         transform.position = Vector3.MoveTowards(transform.position, target.position, step);
22.     }
23. }
24.  

I have rigidbody constraints and a collider but the object moves in any rotation and direction and it clips through objects, how do I fix this?