Welcome!

Personally I would avoid any sugar. It just adds unnecessary calories.

I save all my 500 cal for one meal at dinner. During the day I drink tons of green tea or water. We all have to find our own ways how to tolerate our fasting days. Some eat more than one meal, albeit smaller ones. I found sugar free chewing gum helps.
Best of luck
Stef.

Welcome to the forum mitziwillow2u.
It always helps to drink lots of water on fast days, I prefer sparkling water or lemon tea. Its up to you how you take your tea, but don’t forget to subtract the calories for milk and sugar from your 500 fasting allowance. I think I would just forget the sugar but I do allow myself milk in tea on a fasting day.
You will find your fast days get easier the more you do, and even on normal days your eating habits subconsciously change (for the better).
Take your measurements, particularly waist and weight, and calculate your TDEE here
http://thefastdiet.co.uk/how-many-calories-on-a-non-fast-day/
and on normal days try to eat above your BMR and below your TDEE then recalculate it as your weight drops 🙂
Good luck with this way of life I am sure as you read around the forum you will find motivating stories and realise this is a sustainable way to a lighter and healthier life 😀