Any advice to get through the first few days ?

I am really truly striving to stop drinking and smoking. It’s so pointless. I’m actually starting to hate it but the problem is I been having health issues for about two years straight now where my stomach feels absolutely terrible every single day. (Constant pressure, constipation, and lack of appetite) after going to see doctor “experts” for about two years and coming up with 0 answers the only thing I could come up with is 2-4 small bottles and smoking a joint of weed. I do get some relief once I do it but it’s surely just a bandaid on a gun shot wound type of fix and it’s definitely time to try something else. I also used to take Percs, Xans, Promethazine, Suboxones but have been clean from them for 3 years.

I guess my overall question is if I feel terrible every single day for 15+ hours of it how can I even start the journey of sobriety ?