You should be fine doing cardio after lifting. Not a problem. I’ve done it. As far as eating, I would get a meal in as soon as you are comfortable. You will lose more fat based on your total calories for the day, rather than how long you wait after weight training and cardio. In fact, getting in a meal sooner will probably help you maintain/build more muscle, which will only help your fat loss goals along. In short, waiting is not maximizing fat loss (I know the cardio on empty stomach thing is popular these days, but it doesn’t paint the full pictures) – maximizing fat loss is burning calories and consuming the right amounts of food. Training and timing will ensure you maintain/gain muscle.