Helping others, such as those trying to cope with serious mental health issues, can be rewarding. You really can help those who try to help themselves. Giving them good and helpful advice matters too.
However, you don't want to tell those who you are trying to help how they should run their lives, even if you have the best of intentions.
Years ago, I knew a guy who years before then was a mental health worker. And although he meant well, he was always telling others how they should run their lives and what they should do. He did that with me sometimes, even though I never even asked for his advice in the first place.
I wouldn't have wanted to have him as my mental health worker!
So if you try to help others, do what you can. But don't tell them how they should run their lives. It won't go over well with anybody, I think.