Fasting is not consuming any calories for a period of time, so don’t drink anything with calories.
Some people are a bit more flexible with the word and still consume amount of calories during the fasting period, but if you’re going to do that I’d at very least avoid simple carbs like sugar. In my experience they really tend to boost my hunger.
> and when is the best time to eat
Even if there’s a theoretically optimal time, how well it works with your life is magnitudes more important than that. No point in picking what’s theoretically optimal if you can’t actually sustain it for long enough to achieve your goals.
Can’t you put your eating windows before~during work if you don’t feel well with it after work?
And honestly, to some extent I’d argue that the same applies to eating window and frequency. Not everyone feels well with intermittent fasting and can accommodate it in their routine, and if you’re feeling like you’re one of those then maybe it’s best to try something else.