Tips for extended fasting?

To those who benefited from doing a 7 day fast (or close to it) what did you eat and how often before beginning it? Any recommendations for consistent electrolytes or ways to ease discomfort during it? Also how did you resume eating normally again?

I’ve tried intermittent fasting several times and it just doesn’t provide any noticeable benefits whatsoever so I am convinced to do the long haul fast. I would hope this produces something favorable, otherwise I have no idea what would at this point.