Give me a proven way, maybe even a few. I need everything you can give me. My brother is trying to quit smoking and is very worried that his willpower is weak.

The fastest way that I know is to use CBD oil in the first three weeks after quitting nicotine. You can check this site hyperlink. There are different types of CBD, but it seems to me that the treatment principle is the same for them. You can buy vape oil or lozenges. It will still be good to stop the craving for nicotine.