If you are a smoker, you can still obtain a life insurance policy. You will, however, pay a higher premium than a non-smoker. If you have been smoke- free for over a year, you can qualify as a non- smoker with many different companies.
If you have a smoking related illness, the life insurance company may not provide you a policy. It will be considered based on severity, curability, and if, it will affect your life span. You still may be able to purchase a policy but the coverage amount will most likely be a small amount and the premiums will be on the higher side.
If you become smoke- free after you have purchased a smokers policy and stay that way for a certain period of time, your insurer may issue you a policy at a lower rate.