How to tell my dad? please, help needed!!!?

Well, i hope your friends didn't pressure you into doing this because they're not friends.. Tell him about your addiction he could probably help, im sure 1 of your slip ups will not make him leave. He's a great father just tell him your feelings, how you don't want to do it anymore and you want help etc. He'll probably get you in a rehabilitation center . I'm sure he'll be mad, but Your health is what's more important. Trust me he wants what is best for you. He doesn't want to see his step child on drugs. So it would be best if you did it now . I hope things really work out for you :)!!!