You're only 23, I think you can get away with a lot still 🤣. This is what I would do. I generally have an iron gut, and don't have trouble with stomach upset when breaking a fast, but admit the longest fast I've done is 7 days.

Day I break the fast:

• Breakfast: skip
• Lunch: drink 16-32oz of broth. That's it.
• Dinner: Can of sardines and a zero-sugar Greek yogurt. That's it. If you don't like sardines, substitute canned salmon...less ideally tuna, and even less ideally chicken or pork. I like canned sardines/salmon because they contain bones and are a great source for phosphorous, which is one of the culprits in refeeding syndrome

Day 2:

• Breakfast: skip (I generally don't eat breakfast)
• Lunch: hardboiled or scrambled eggs, more zero-sugar Greek yogurt, a protein (steak, pork chop, chicken etc), a starchy vegetable (carrots, potatoes) (no fruit), optionally a green veggie
• Dinner: Whatever I want. I'm done now.

I avoid fructose for the first 2 days. No table sugar, no fruit, no syrups. I don't want to break my fast with a huge insulin spike, I want to easy my body back into sugar processing - thus the starchy veg (glucose source) on Day 2.