Assets\PlayerMovement.cs(5,44): error CS1003: Syntax error, ',' expected

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

public class PlayerMovement : MonoBehaviour;
{

public CharacterController2D controller;

public float runSpeed = 40f;

float horizontalMove = 0f;

// Update is called once per frame
void Update()
{

horizontalMove = Input.GetAxisRaw(Horizontal) * runSpeed;

void FixedUpdate ();

// Move our character
controller.Move(horizontalMove * Time.fixedDeltaTime, false, false);

}

}

horizontalMove = Input.GetAxisRaw(Horizontal) * runSpeed;

void FixedUpdate ();

// Move our character
controller.Move(horizontalMove * Time.fixedDeltaTime, false, false);

}

}

change public class PlayerMovement : MonoBehaviour;
with public class PlayerMovement : MonoBehaviour

why would you close the body there?

you want to create a new class body … not close it

Another note …

it doesnt work since your syntax is broken,

void FixedUpdate ();

that wont work,

also you got 2x fixedUpdate and so on …