Who controls USD?

Who exactly holds the reins of the US dollar? Is it the Federal Reserve, or does Congress play a pivotal role? Could it be the hands of individual banks and financial institutions that shape its flow? Or perhaps, is it the collective will of the American people that ultimately determines the value and stability of the greenback? The question of who controls USD is not a simple one, as it involves multiple layers of power and influence. Could you help me untangle this web of authorities and explain who really calls the shots when it comes to the world's reserve currency?