Methods To Quit Smoking

I’ve been smoking weed pretty much every day for the last 3 years…I’m 23 now and I really want to stop, but it’s pretty hard to. I know I cant really go to rehab for pot, so what can I do to kick the habit once and for all?

My dad has suffered from serve mouth ulcers since he was a little boy, but when he begins to smoke they stop, but he has quit smoking now, and his ulcers are so big, they are like holes in the side of his mouth, and it causes him terrible pain. But the doctor told him to take vitamin tablets, but my dad has been taking them for like a year now, and the ulcers just seem to be getting worse. What can he do, or what should he do. He is aged 46, and has a very good diet and is average in health.