I think it's laid out like this:
1. Stop killing yourself with sugar, wheat and industrial seed/veggie oils. There are folks who can be healthy on wheat, but most folks that are really overweight, and thus presumed carbohydrate intolerant for the short term, there's no upside to wheat and many downsides.
2. Part 1 can take a while. It took me from 1996 to 2007 to finally burn my hand on the stove often enough that I could let go of routine doses of sugar. Something happened in 2007, in which I began to perceive most sugary "treats" as "industrially produced crap that treats the food industry at my expense." I learned not to like that crap, not to want that crap. My unconscious association changed. After part 1 is well under way, it is worth thinking about the rest of the list:
a. More grass fed meat, less industrial produced meat. Wild game and grass fed beef = good!
b. Finding a source for raw, un-pasteruized milk, if you like milk and are milk tolerant
c. Can you get locally grown veggies at the farmer's market?
d. Experiment and measure the results of supplementation of various micro-nutrients. Potassium, vitamin D, vitamin K, magnesium - most folks find some benefit from taking these. But it can be a challenge to find the formulation that benefits you most. Some can take any old ZMA and feel a benefit, others love for example Natural Calm, and others another variety. The complexity also gets worse, not better - a product that produces a good response initially may eventually not be as potent as the body improves in health, so the search for impactful doses and formulations continues.
e. Are you willing to try fermenting foods? I'm not, but my lovely bride is - and I like them quite a lot. Fermentation seems to bring good bugs back to the gut.
f. Bone broths have been a human staple - again, thanks to Janet I am learning to love them. They seem to help health the GI tract from the various injuries we inflict upon it via wheat/grains, sugar and related dysbiosis, FODMAPs, etc.
g. Eating more veggies falls in here too - if you are pounding down sugar and wheat, I doubt increased veggie intake will make much difference that a person could discern, or in any health markers. I liken it to trying to put out a fire with a squirt gun, when the real solution is to turn off the gasoline spraying from the broken fuel pipe (IOW stop the wheat and sugar).
h. Lots of people are sensitive to dairy, eggs, wheat, or some other food source, and have no idea. Tests for food allergies are easy and relatively cheap. Some folks can do nothing more than stop eating sugar/wheat and their allergic food, and feel MUCH better.
i. Sleep - sleep is kind of like step 1, in that it affects all other factors of health. You if you don't sleep well, you can still reduce the damage by sticking to step 1 (but bad sleep makes step 1 harder).
j. Dealing with distress. You can end stress only by dying. You can reduce the distress in your experience many ways, but the evidence is piling up that a formal relaxation practice of some sort has a potent and positive health impact.
k. Dealing with aspartame, OTC meds and other neolithic "downers". This had no where near the impact for me that other steps did, but it was a positive step nonetheless to go from a gallon a day or so down to the 3-4 aspartame drinks I have now.
Why do all of these things work? They allow the gut to heal. They allow a healthier gut biome. They allow the liver to heal and work more efficiently. They allow your cells to regain a more normal insulin sensitivity. The reverse the body's abnormal responses to abnormal quantities and types of foods. They let your hunger work like it is supposed to work - to keep you from starving to death without making you eat more than you need. Your body is a finely honed machine, refined by thousands of years of adaptation. These changes allow the machine to work as designed.
All these changes are easier said than done. You have to fail to succeed - at least, most of us will have to. And that's OK - if you get the sugar/wheat out of your diet or 2 months, you gave yourself two months of healing and likely some lessons that will inform future success.
In summary - if health becomes the thing that matters to you, there's a long trail of learning to follow. It might require eating a bunch of veggies at some point. Start where you are, put a foot out and keep moving towards the vibrant, healthy you that feels good most days.