How to get the movement direction relative to a character

I cant seem to understand your answer :/ can you please elaborate a little bit? Like transform.forward -transform.forward = 0

no i mean

if you want to get 1 unit ahead of the player its position/direction is

 player.transform.forward

if you want to get 1 unit behind the player

ITS NOT

 player.transform.backward

that doesnt exist

IT IS

 -player.transform.forward

this is an example of a script you can attach to the main camera that will move the camera forward/backward/left right/ based on you pressing W A S D

 public class $$anonymous$$oveCamera : $$anonymous$$onoBehaviour {
     Transform cam_tran;
     public float move_speed;
     // Use this for initialization
     void Start () {
         cam_tran = Camera.main.transform;
     }
     
     // Update is called once per frame
     void FixedUpdate () {
     if(Input.Get$$anonymous$$ey($$anonymous$$eyCode.W))
         {
             cam_tran.Translate(Vector3.forward * move_speed * Time.deltaTime);
         }
     if(Input.Get$$anonymous$$ey($$anonymous$$eyCode.A))
         {
             cam_tran.Translate(Vector3.left * move_speed * Time.deltaTime);
         }
     if(Input.Get$$anonymous$$ey($$anonymous$$eyCode.S))
         {
             cam_tran.Translate(Vector3.back * move_speed * Time.deltaTime);
         }
     if(Input.Get$$anonymous$$ey($$anonymous$$eyCode.D))
         {
             cam_tran.Translate(Vector3.right * move_speed * Time.deltaTime);
         }
     }
 }

you will notice it has a backward and left. Thats because vector3 does have a backward and left although these are just equal to 0 0 1 and -1 0 0

most gameobjects do not have a left you use -right

Thanks for helping sparkzbarca :) , I understand that now. But after searching deeply, I found my answer somewhere in the unity answers, my bad, I didn't searched that deep before asking, sorry for bpthering you guys :/