It partly depends on your goal / ideal body fat percentage; however, it's easier to start with a cut so you're at a good base to make lean gains, since once fat cells split and multiply they cannot be removed; you can only shrink them. Metabolism is often fatest in the morning, due to effectively fasting over night, and this is the reason many people like to exercise early.
I would find a program that uses compound movements to engage all major muscles. This is only a ballpark figure, as body type and hormones play a role, but 50% protein, 25% carbs and 25% healthy fats is a fair estimate for lean gains, give or take some of the percentages. Consuming 6 small healthy meals per day produces a greater anabolic effect and boost to metabolism than 3 large meals.
As for exercise, 3x a week resistence training, with a 20min HIIT workout after one or two of the sessions promotes the breaking down of fat stores and burning of free fatty acids, since EPOC requires more energy to recover following a workout and causes the body to increase its fuel consumption, meaning an elevated metabolic rate even at rest afterwards.