I think I suggested it before but I highly recommend the book, “The Easy Way To Stop Smoking” by Allen Carr. Quitting by reading a book sounds ridiculous but I quit a 40 plus year habit and it was one of the easiest things I EVER did! It’s basically Cognitive Behavior Modification and uses a whole different mental approach than what smokers are used to. Carr encourages you to smoke along as you read. By the end of the book I didn’t want to smoke but, as encouraged, I had one last cigarette when I finished reading and havent looked back. I havent had a cigarette in over 4 years and haven’t been tempted once. I can’t believe I ever smoked. The book can be bought for around $13 on Amazon or can be found for free in your local library. Do your dad a favor and buy him a copy. I suspect he’ll ditch that last one a day smoke easily.