Ok so I have this friend he's a guy I'm a girl and I just found out ( not from him) that he has been drinking smoking and occasionally doing weed. He's only 15 I'm scared to death the person who told said not to tell anyone or he will run away but in so scared! He says he's getting help but how can I be sure? Should I talk to him about it?

I think you need to talk to a trusted adult about this. If not your Mom or Dad, then maybe a teacher. Someone who will be able to help him without scaring him into running away. If you could persuade him to approach a trusted adult himself, it would be even better. You could offer to go along with him. If he was telling you the truth about what he is doing, then I think he was looking for some help. Offer to be there for him and keep an eye on him but make sure you have the support from your parents or a teacher before doing this. It can be a dangerous world out there and you are to young at 15 to be dealing with this by yourself. If you are not sure how to approach a trusted adult you could show them your question and this answer. I hope this helps.

I'm actually 17 it's just my friend that's 15

And I swore I wouldn't tell

He's behaving in an irresponsible and dangerous fashion. If you swore you won't "tell" and don't feel this is serious enough to break that promise you have two choices - try to change his mind about drinking/smoking OR do nothing.

There's no middle road here.

I note you are 17 now but were 18 last November (when people spent time and effort answering you as a legal adult with problems) on more than one thread so, what's really going on? https://www.askmehelpdesk.com/other-business-careers/hate-job-715056.html If you are, in fact, the answers on the other threads did not apply to you as an underage person.

This is actually my friends account that's why the age difference But I think I will try to talk to him next time I see him

The accounts are easy and free - please open your own account.

Using someone else's only causes problems. In this case your friend's integrity has now been called into question -

This is actually my friends account that's why the age difference But I think I will try to talk to him next time I see him
Whatever your age is, HIS age is only 15 and he needs help. It does not matter if you swore you wouldn't tell. He could be in danger and protecting him from himself is more important than his feelings about you. I think you said before that he originally told someone else so he seems to be reaching out for help anyway. Please tell someone you can trust now. Please don't leave it. I don't know what age you really are but he needs help from a responsible adult. You can get him that help. I'm actually quite upset about this because I have a son who is a similar age and I would be devastated if I thought this was happening to him, especially if he had reached out to someone and they had spent the day dithering about getting help for him on sites like these. I cannot stress this enough - please go and talk to a teacher or your parents now.

I told my mom and I feel much better thank you for the advice I hope he can get help now and learn his lesson

I told my mom and I feel much better thank you for the advice I hope he can get help now and learn his lesson
Well done, you did the right thing for your friend.