How to make players follow only the movement but not the position / vector.

First of all, sorry for my English.

I am now doing 2d top down game. I want when I move my player to the up/down or left/ right, another gameObject will follow even it is not in a same position / vector. At the same time it was in the mirror movement. I mean when I move right, it will move to the left. But if I get stuck on some collider but still pressing forward button, that gameObject will still moving forward if there is no collider in front of him.

Here is the code I use and work perfectly in mirror effect movement. But I cannot achieve what I want using this code. I want to know:

1) How can I make the gameObject still moving forward (no collider in front of him) when I pressed forward button even if I stuck on some collider.

2) How can I stop the gameobject from going through the wall?

     using UnityEngine;
     using System.Collections;
      
     public class Mirror : MonoBehaviour {
      
     public GameObject mirrorObject; // Object to mirror
     public bool mirrorX; // Wether or not to mirror the X axis
     public bool mirrorY; // Wether or not to mirror the Y axis
     public bool mirrorZ; // Wether or not to mirror the Z axis
      
     public bool useLateUpdate; // Wether or not to set the object's position in LateUpdate
      
     void Update()
     {
     Vector3 newPosition;
     newPosition = mirrorObject.transform.position; // Get the mirrorObject's position
      
     if(mirrorX)
     {
     newPosition.x = -newPosition.x; // Mirror on the X axis
     }
     if(mirrorY)
     {
     newPosition.y = -newPosition.y; // Mirror on the Y axis
     }
     if(mirrorZ)
     {
     newPosition.y = -newPosition.y; // Mirror on the Z axis
     }
      
     if(!useLateUpdate)
     transform.position = newPosition; // Set object's position equal to the new mirrored position
     }
      
     void LateUpdate()
     {
     if(useLateUpdate)
     transform.position = newPosition; // Set object's position equal to the new mirrored position
     }
     }