You seem to be having physiological acne. This acne is due to underlying hormonal change that is normal at your age. What is not normal, however, is the marks being left behind. Use a ph balanced salicylic acid face wash twice a day. Use a gel based sun screen regularly. Avoid picking at or squeezing acne as it can cause more marks.
Eat plenty of fruits and vegetables and drink plenty of water. Avoid junk foods and exercise regularly. Avoid smoking.
If marks persist or if you get depressed scars you may need tablets for this condition. Please contact a dermatologist who can examine you and prescribe the appropriate skin care products and treatments