Player Controller "Horizontal" input convert to "left" and "right"

I am currently creating a game in which the player can drive around on a spherical planet. I wrote the code below with original intentions of publishing it on a pc platform but I decided to convert it over to mobile. What I would like to do is convert what is in the fixed update into two separate voids: a left control and a right control (idk if that makes sense). I guess what I am trying to say is how would I convert

rotation = Input.GetAxisRaw(“Horizontal”);

into a left and right void? Thanks

public float rotateInBetween = 4f;
public float rotateAdd = 25f;
public float moveSpeed = 5f;
public float rotationSpeed = 200f;
public float accelerationAddSpeed = 0f;
public float accelerationInBetween = 0f;
public float slowMotionLength = 3f;
public float animationSlow = .2f;

private float rotation;
private Rigidbody rb;

void Start()
{
	rb = GetComponent<Rigidbody>();
    StartCoroutine(rotateSpeedAdd());
}

void Update()
{
    if (Input.GetButtonDown("Fire1"))
    {
        StartCoroutine(timeSlowPowerUp());
    }

    rotation = Input.GetAxisRaw("Horizontal");
    rotateSpeedAdd();
}

void FixedUpdate()
{
	rb.MovePosition(rb.position + transform.forward * moveSpeed * Time.fixedDeltaTime);
	Vector3 yRotation = Vector3.up * rotation * rotationSpeed * Time.fixedDeltaTime;
	Quaternion deltaRotation = Quaternion.Euler(yRotation);
	Quaternion targetRotation = rb.rotation * deltaRotation;
	rb.MoveRotation(Quaternion.Slerp(rb.rotation, targetRotation, 50f * Time.deltaTime));
	//transform.Rotate(0f, rotation * rotationSpeed * Time.fixedDeltaTime, 0f, Space.Self);
}

I don’t know if you want to check for other input rather than the horizontal axis but you could check in the fixed update if the Input.GetAxisRaw(“Horizontal”) is greater than zero or below zero. One of them is left and one of them is right.

So something like:

void FixedUpdate (){
 if (Input.GetAxisRaw("Horizontal") > 0) {
  //Left??
 }
 if (Input.GetAxisRaw("Horizontal") < 0) {
  //right??
 }
}