There is an excellent video MADE FOR YESHIVA BOCHURIM by Rabbi Shaul Cohn of Boston,Mass.about the dangers of smoking.
I personally purchased a few of them: One to show my own bochurim, and the other 2 I sent to my sons’ yeshivos.
Rabbi Shmuel Kaminetzky (shlita) personally introduces the presentation,followed by the fellow who
shows (with video clips and other visual info.)JUST HOW BAD SMOKING IS….and how many addictions start from “just trying one cigarette”.I highly recommend it.