I really needed advice years ago when i started developing my Ed, so I'll give some advice to y'all. I don't promote this in any shape or way, but this is just gonna help u instead of making yourself suffer. When you start to fast, remember before you actually do even 24h fast:
Remember to, slowly make your daily food intake smaller and smaller.
Drink water so ur stomach gets used to you drinking water instead of feeling suddenly nauseous.
Try to eat low call foods before fasting, like cherry tomatoes, eggs or anything else low in calls.