Answered[ Edited ]
To combat acne, I would suggest both some Sephora Products and a non-Sephora product, though all of the products I'm suggesting are very affordable:
Because, you're young and still have a lot of natural beauty, it would be best to to use natural products that willl control oil and fight blemishes without overdrying you skin. The best skincare regimen I know of to combat oily skin is actually quite affordable and is now sold by Sephora: The Body Shop Tea Tree Oil skincare products. The best value for you would be The Body Shop "Tea Tree 4-Piece Facial Skin-Care Regime" (Sephora Product Page)
For under $30, you receive the following products:
"Tea Tree Skin Clearing Facial Wash" A gel-based cleansing facial wash that removes excess oil without over-drying the skin.
"Tea Tree SKin Clearing Toner" A refreshing toner that removes traces of cleanser, makeup, and impurities.
"Tea Tree Skin Clearing Lotion" This is the ideal moisturizer for oily skin because it provides hydration where you need it but helps keep oily spots mattified.
"Tea Tree Oil" An effective spot treatment that reduces the appearances of blemishes overnight.
If you prefer, all 4 of these products can also be purchased separately at Sephora. These products have helped my skin produce less oil and treated and prevented breakouts without overdrying or being too harsh on my skin, so I think they would work great for you. Also keep in mind that they are very natural: without parabens, sulfates, synthetic fragrances, triclosan and petrochemicals.
If you have a problem area on your face that gets really oily, you might need a spot treatment that's stronger than the "Tea Tree Oil." For that, I recommend Neutrogena "On the Spot Acne Treatment." This product is very effective, but doesn't have too much benzoil peroxide, so it shouldn't dry out or irritate your skin. Sephora doesn't sell this product, but you can buy it online at Ulta Beauty for about $6.
I hope this helps!