It depends. Most people say you should. But, if you find that your skin is super dry, using the powder on top can sometimes make the dryness more noticeable.
Getting good with make up does take practice and finding what products and technique works best for you.
Regarding skin tone... best way to figure it out, is look at your veins on your arms - if the veins have a blue tinge to it, then you are cool toned, if the veins look more green, then it's likely that you are warm toned. But tha