Meal Timing
I don't have strict rules for when you eat or do your workout. However, I do recommend that you wait 2-3 hours after eating to allow your body time to digest before exercising -- unless it's just a small snack, which is totally fine.
The only time I suggest that you be strict about not eating before a workout is if you are on intermittent fasting (IF) and your workout time falls during your fasting period. Though it can be incorporated, intermittent fasting isn't part of the 21-Day Metabolic Reset or Eat360, but I mention it here for those already doing IF or considering it.