GameObject instantedBomb = Instantiate(bombPrefab, new Vector3(posX,
            bombPrefab.transform.position.y, posY),
            bombPrefab.transform.rotation);
            var script = instantedBomb.GetComponent<Bomb>();
            script.player = gameObject;

Bomb:

public Component player;
    private void AddBombInt()
    {
        player.addBomb();
    }