In order to not die you have to eat healthy. You can eat foods that are "bad" every once in a while, but eating them every meal can lead to long term diseases like diabetes.
You can also eat well by limiting how much you eat. If you eat slightly less than before you might see a difference.
Smoking is a big gateway to cancer. The main cancer you get from smoking is lung cancer. Most people who get lung cancer die from it. In order to help avoid lung cancer don't smoke.
Vegetable are good for you because they provide you with vitamins.
Working out and staying healthy can help decrease your chance of getting sick.
You don't have to go to the gym and work out. Just being active can help decrease your chance.