I tried my best to explain it as simply as possible, but it was still difficult for you ㅠㅠ The version I was explaining might not have been the latest one, which could have made it even more challenging for you. Docker and docker-compose can feel quite difficult at first, but once you get the hang of it, it feels like nothing at all, so don't give up and why don't you try going through it again step by step + making sure not to skip the hands-on practice?