Wanting to help others is a noble cause and you should be proud that you are considering this step. However, it is important to provide help in a meaningful and constructive way, so that you do not worsen the problems that are affecting the person you wish to help.
To this end, CryptoSamaritan has some useful resources and suggestions if you do wish to try to help those suffering from addiction or depression. If you are suffering from these problems, please focus on yourself first and foremost so that you do not fall into a spiral with the person you are trying to help.
Remember: Someone who is addicted or depressed cannot be helped simply within a day, and you cannot help them alone. When helping someone with a serious mental health issue, your primary goal should be to get them to willingly visit a professional, such as their doctor or a mental health expert, as this is the most effective way to help them.
This can be difficult, but it provides the best outcome. Thank you for your help in advance.