It took me 8 years to stop smoking.
In regards to diet, the way I did a reset was to start with continuing everything I was doing but eliminating one thing that I ate to excess, which was icecream.
Then went like this (just typibg out what worked for me in retrospect).
Find a healthy alternative like greek yoghurt and Berries with nuts. The point of this phase isn't to lose weight, its to wean you off sugar.
Continue to allow some kind of treat in a small format, daily square of dark choc etc.
Replace other unhealthy things, if it's crisps choose healthy crackers or breadsticks instead. Something you don't like enough to binge on. The point again is to wean yourself off processed foods.
Crowd in veggies and healthier foods.
Then introduce calorie counting. Just do a small 100-200 calorie deficit.
You can probably keep going for 8-12 weeks of steady weight loss like this. Then you are on a roll!
Then to continue to lose weight after this cut calories further and exercise more. Only do this if you actually still have weight to lose. That's when something like fasting 5/2 or F800 might help. These are not sustainable ways of eating but they are based on the Mediterranean diet which is a good exit plan anyway.
Also track everything. Don't beat yourself up, it's a process and I think August is probably a hard month to start dieting, this time of year generally is hard as I think the body is hard wired to think this is harvest season.