2d Car Movement (2d Physics)

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CarMovement : MonoBehaviour
{
    public static CarMovement Instance;

    //making public varaible for image
    public UnityEngine.UI.Image image;

//fuel
    public float fuel = 1;

//engine burning the fuel
    public float fuelconsumption = 0.1f;

    //Speed for the car will move
    public float speed = 1500f;

    public float rotationSpeed = 15f;

    //ref to back wheel
    public WheelJoint2D backWheel;

    //ref to front wheel (also this is the Torque)
    public WheelJoint2D frontWheel;

    public Rigidbody2D rb;

    private float movement = 0f;
    private float rotation = 0f;

    void Awake()
    {
        Instance = this;
    }

    //This is for user input
    void Update()
    {
       movement = -Input.GetAxisRaw("Vertical") * speed;
       rotation = Input.GetAxisRaw("Horizontal");

        //it counted in frames
        image.fillAmount = fuel;
    }

    //This is where we DO the movemnet
    void FixedUpdate()
    {
        // check if the car will be moving

        //fuel checker

        if (movement == 0f )
        {
            backWheel.useMotor = false;
            frontWheel.useMotor = false;
        }

        else if(fuel > 0 )
        {
            Debug.Log("We have fuel");
            backWheel.useMotor = true;
            frontWheel.useMotor = true;

         // you can also make it "1000" rather than = "backWheel.motor.maxMotorTorque"
            JointMotor2D motor = new JointMotor2D { motorSpeed = movement, maxMotorTorque = backWheel.motor.maxMotorTorque };
            backWheel.motor = motor;
            frontWheel.motor = motor;
        }
        rb.AddTorque(-rotation * rotationSpeed * Time.deltaTime);
        fuel -= fuelconsumption * Mathf.Abs(movement) * Time.fixedDeltaTime;
    }

}