Addiction

My older brother just confessed to me that he is going through substance abuse and is addicted. He told me wants to seek help and go to rehab because he has a daughter and he’s very scared for things to go bad. As his sister I’m willing to help him 100% but have no idea where to even start or how much the cost is. Idk what to think or do rn. My mind is blank and I’m just hurting. Our relationship was never the best but knowing that he came to me asking for help just shows how serious he is about it. Any advice or kind words would be appreciated. I’m just kinda scared rn.