If you are going to be moderately active you should aim for 1800 or more calories for your age (if you are a boy). At 13 you are still growing, so you will definitely want to be gaining some weight but you can aim for not gaining 'fat' weight and just 'muscle' weight. So try 1800 for 1-2 weeks and see how it goes and how you are feeling and then adjust as you go. The mirror will probably be a better tool than the scale to tell you about your progress.
On 1800 calories you should aim for 60-130 grams of protein each day. Go for the higher end if you are working out that day. Pretty much if you include protein in each of your meals and include a lot of variety in your proteins, grains and veggies you should be set. Go for whole grains - they have more protein than processed ones.
I would recommend cardio after your workout. You want most of your glycogen energy available for lifting . Amount of cardio is up to you, but I always prefer shorter (15min) at a higher intensity.