Hi ! Consult a dermatologist who can suggest procedural treatments like chemical peels which can help in controlling the acne as well as target the black marks.
Next Steps
Start using a dermatologist prescribed sunscreen with an SPF of 30 . The sunscreen has to be applied once in 3 hours especially between 7am-5pm on all days irrespective of the climatic conditions and your activities.
Health Tips
Do not invest in over the counter medications !