move a rigidbody with WASD (hovering)

ok to start i have a sphere that i applied this C# script to that makes it hover exactly how i want it to, but for the life of me i cannot get WASD to move it relative to itself
W/S should move forward and backward
A/D is strafe
i dont have any of my fail attempts in the hover code just the hover code itself, thank you for any help

using UnityEngine;
using System.Collections;
 
public class HoverScript : MonoBehaviour 
{
    public float hoverDistance = 0.75f;
    public float hoverForce = 10.0f;
    private float currentHeight = 0.0f;
    private float hoverForceMultiplier = 0.0f;
    private Vector3 hoverForceApplied = Vector3.zero;
 
    void FixedUpdate() 
    {
        // -- find hover distance and add force to make hover   
        RaycastHit rayHit;
        if (Physics.Raycast(transform.position, Vector3.down, out rayHit))
        {
           currentHeight = rayHit.distance;
           if (currentHeight < (hoverDistance - Time.deltaTime))
           {
             // find percentage of currentHeight below hoverDistance
             hoverForceMultiplier = (hoverDistance - currentHeight) / hoverDistance;
             hoverForceApplied = (Vector3.up * hoverForce * hoverForceMultiplier) + (Vector3.up * 9.8f);
             rigidbody.AddForce(hoverForceApplied);         
           } else {       
             // apply anti-gravity force for half distance above hoverDistance
             if ((currentHeight - hoverDistance - Time.deltaTime) < (hoverDistance / 2))
             {
              hoverForceApplied = (Vector3.up * 9.8f) * ((hoverDistance - (currentHeight - hoverDistance)) / hoverDistance);
              rigidbody.AddForce(hoverForceApplied);
             }
           }
        }
    }
}

Do something like this to add a left-right force:

rigidbody.AddForce(Input.GetAxis("Horizontal") * transform.right * ForceMagnitude);

And this to add a forwards-backwards force:

rigidbody.AddForce(Input.GetAxis("Vertical") * transform.forward * ForceMagnitude);