How to give an image to a sprite in c# code?

I am making a game with where the main character shoots a gun. I have made it so each time the player presses "E" it creates a new bullet, a collider as a trigger (to check if it hit a target), some code to tell it how to move and a sprite renderer but when I can't figure out how to give the sprite renderer a picture. I tried using file paths but, I have no clue what I am doing. My code looks like:

 string bulletPath = "../Assets/Fighting/Bullet.png";

if (Input.GetKeyDown("e"))

         {

             GameObject Bullet = new GameObject("Bullet");

             BoxCollider2D hit = Bullet.AddComponent<BoxCollider2D>();

             Bullet.AddComponent<Bullet>();

             Bullet.AddComponent<SpriteRenderer>();

             Bullet bullet = Bullet.GetComponent<Bullet>() ;

             SpriteRenderer renderer = Bullet.GetComponent<SpriteRenderer>();

             renderer.sprite = Resources.Load<Sprite>(bulletPath);

             hit.isTrigger = true;

         }

If you have any suggestions they would be greatly appreciated