I'm sorry to hear that. You've been poisoned by the American corporate driven diet.
Eating paleo is what started to change my life. I made it my own from there. It's my lifestyle, not a diet. I'm 39 and have numbers consistent with the average person in their 20's. Avoid the real unholy trinity and you're life will increase drastically: Sugar, wheat, and Dairy. All of the artificial sweeteners and chemicals have to go for your mental and physical health. Good fats. Cut grain down, and eat meat, fruit, and vegetables. Black coffee with almond or oat milk. Water. Unsweetened tea.
Practical Paleo is a great book to read. It's half easy to read nutritional education and half easy recipes.
Or, just let them kill you slowly. 80% of people in the medical field have never had even a misguided class on basic nutrition. Find the root cause, don't just bombard it with profitable medicine.
As far as eating utter garbage food we're all intentionally driven to, there are always cheat days. Pizza and beer nearly kills me, but it's frequently part of a couple cheat meals each week.
Exercise is great for the body and mind. Don't overdo it if you're not used to it. Even speed walking and light jogging intervals for 20 minutes a few days a week is a good way to ease into it and make it a normal part of your routine.
Sorry for going off topic. This isn't a rant as much as I hope even a complete stranger will red pill their nutrition. Especially when they're facing terrible illness.
RFK's podcast has a ton about the American diet and how the money driven big food teamed up with big pharma are killing us. Even if you don't like Tucker Carlson (everyone should listen to opinions they don't like) Calley and Casey Means were on a podcast recently that really sheds light on this topic.