How to move player according to where camera is facing.

hey, I would like to know how you can move the player according to where the camera is facing, I can move the player and make the camera "look" but when I press the forward key which is W to move the player forward while I'm facing right the character will move left to where I'm look , if that makes sense. and I don't want to use the standard assets I want to do it by scratch..if it's still not clear ill give another example,

so I moved forward by pressing W but then I look right by moving my mouse right and I try and move forward in that position but I don't instead I move left in that position since left would be forward. my scripts:

 //really simple movement script , nothing complicated, this script snippet is from a script called player 
 void Update () {
         
         
         Vector3 moveInput = new Vector3 (Input.GetAxisRaw ("Horizontal"), 0, Input.GetAxisRaw ("Vertical"));
         Vector3 moveVelocity = moveInput.normalized * moveSpeed;
         controller.Move (moveVelocity);
         

my other script which had the method "move()":

 //this script  is called player controller and it has the move function which the player script calls. the bottom of the script is the actual movement

using UnityEngine; using System.Collections;

[RequireComponent (typeof (Rigidbody))] public class PlayerController : MonoBehaviour {

 Vector3 velocity;
 Rigidbody myRigidbody;

 void Start () {
     myRigidbody = GetComponent<Rigidbody> ();
 }

 public void Move(Vector3 _velocity) {
     velocity = _velocity;
 }

 public void LookAt(Vector3 lookPoint) {
     Vector3 heightCorrectedPoint = new Vector3 (lookPoint.x, transform.position.y, lookPoint.z);
     transform.LookAt (heightCorrectedPoint);
 }

 void FixedUpdate() {
     myRigidbody.MovePosition (myRigidbody.transform.localPosition + velocity * Time.fixedDeltaTime);

 }

} I really hope someone can help , thank you, btw its a top down/ first person shooter thank you again.