Being an adult involves several different things. From being able to drive and live on your own to being responsible for maintaining a job and paying your bills. It's the moment when a bunch of responsibilities you didn't even know existed become your, and just your, problem. Nobody can be by your side helping you all the time anymore. You are a functional, and sometimes not that functional, adult who has to manage yourself and be responsible for all the things that your parents were taking care of for you. You are not a little kid anymore, and that is a problem. But it's also a blessing. When we think of adulthood, we always think about the negative side of it, all the problems that it brings to your daily life. But we never really think of all the good things that come with it. And I can assure you, there are plenty. I never miss being a child and having someone else decide every step I take. Yes, I have a lot more on my plate than I used to, but that is exciting. I finally get to do whatever I want, and so do you.
In the case of this kid, who is not a kid anymore, he has every right to decide what he wants to do with his life. Your parents are a part of your life, but they are also adults. They get to decide what they want to do and how they want their lives to be. And, if you are an adult, that doesn't involve you anymore. If they want to live with you and you want to live with them, then do so. But it's not your responsibility nor obligation to do that. You are entitled to decide what you want to do with your life. You have the right to move out, to make your own life choices, to be free from your parents. So stop thinking about what they want from you and think about what you actually want for yourself. You have every right to do your own life as you want to do it.