How can i get rid of this acne on my face and shoulders?

Many options: It depends on the severity and lesion type. You may need an oral antibiotic but may also respond to topical washes too. I recommend you have your dermatologist discuss your particular options.

Acne treament: Trial of 4 weeks with over the counter benzyl peroxide 5 %. If not 50 % better then consult your physician for prescription medication.

Spironolactone: See a dermatologist. For adult women it is all about hormones, menstrual cycles, pregnancies, birth control hormones. The antiandrogen spironolactone is by far the best therapy for this. Takes 3 months to clear acne, then is continued for several years. Very safe. Costs $16 for 3 months. Not to be used if pregnant or nursing or in kindey failure. Avoid potassium pills.