Advice if its ok for me to start smoking or if I should leave it alone?

I am a nonsmoker but weirdly have been craving cigarettes lately. I was tinking what if I just smoked like 3 a day, just how bad would that be for my health....and if I got addicted I dont know if I could stop because I have an 'addictive personality' and its really hard for me to just like stick to a diet. advice? I used to smoke a bit a yr ago but never got addicted. Im 18btw.