How come I can but not for long?

Whenever I try to vape, I sometimes cough, but only after smoking for a determined amount of time. This time is usually abated by me continuing to smoke, but once I vape I can do some hours before I light another ciggy.

1. How come I still smoke
2. When will I quit tobacco use
3. When and how will I quit

These are some of the things that needs to be addressed.

Now if one person would have said that I would have done 42 days as a none smoker. I would have laughed.