Irrespective of appendix operation, you have to stop drinking and smoking. Because both are not good for health. You are just 19 years old. If you start doing those 2 from this age, so many health issues might come. Some of them are excessive weight gain, lung diseases,
liver failure, sexual disfunction, heart problems.
So you better stop them as early as possible.
Next Steps
Stop them and then you can undergo surgery after 2-3 days also. But don't restart them.