Don't fret. We all need some tweaks/changes to both our food and our exercise routines and this board is great for helping with both!
You touched on both topics, but probably better to start with what you're eating and then move on the the exercise (okay, maybe a little summary of what kinds of things you've been doing, we can get into more detail later on.) if the nutrition is off then you're making your exercise results harder to achieve.
While I didn't click around beyond the link you shared to see what they were selling, I think I'd only sort of agreed with like 2-3 of the things on the list as being 'worthless'. Much of their claim to 'worth' or reward/risk/effort to me points more to form than it did the actual exercise. Doing anything incorrectly not only can get you injured but also can really diminish the benefit of the work.
First think I picked up from your intro post was how to get rid of (and keep off) that persistent trouble area(s) without killing yourself every day. ENTIRELY do able! and sustainable! and without deprivation associated with most other 'diets'.
So that said...and a big wave...
lets talk about what you're typically eating and when? Don't have to worry much now about measurements, etc....just the 'stuff'...