It might help if you guys start kind of a self improvement plan together. A plan that involves exercising, diet, doing chores, and having a good sleep schedule (going to sleep early and getting up early). This may be able to help get him outside and start building self esteem, motivation, and confidence. The rock climbing gym sounds like a great idea! His stuttering may be partially due to his parents that are emotionally absent causing him to feel like the world doesn’t care about what he has to say. So maybe it will be important for him to identify that there are people in the world that are more helpful and kind. Maybe try to help him build the confidence to confront his parents and ask them for more support and tell them how he feels about how they have treated him. This will help him get resentments off his chest and also build assertiveness, while hopefully repairing the relationship he has with his parents. I’m not saying that he necessarily needs to gain independence from his family right now, but if he feels like he’s up for the challenge, he should go for it and get his own apartment, etc. I’m 23 and still don’t have a license and live at home, so I understand that we don’t have to push ourselves too much to gain independence, as we can also take advantage of living at home by saving money, etc. Ideally though, your brother might really just need to repair the relationship with his parents or at least try for him to start feeling good. Also man, not to be offensive, but it’s possible that your brother has autism and this is causing his social anxiety. I have been told that I am on the autistic spectrum, and having a therapist (Cognitive Behavioral Therapist, or CBT) has really helped provide me social skills that I feel I lacked. And learning about autism helps me understand myself better. There is actually an Australian YouTuber I watch called “Aspergers from the Inside”, who discusses different topics about his own experience being on the autistic spectrum. Check it out and maybe your brother might relate a bit to it. Because this could also be a missing link to understanding the anxiety that is causing his stuttering. Another book I would highly recommend is “Redefining Stuttering” by John Harrison, someone that stuttered for many years and was high up in the National Stuttering Association for many years. If you look up the book on google you can find a link to it for free. It really goes into the mind of someone that stutters. Hope this helps