You shouldn't eat anything during your fasting window, especially foods that are high in protein or carbohydrates.
However, you can drink water, coffee, or tea during your fasting window, as long as they do not contain any added calories such as sugar or cream.
If you're struggling with hunger and cravings, consider trying our DoFasting Box, a supplement package to be used during your fasting window containing dietary fiber that fill you up and don't break your fast.