Greetings. Pimples may often leave spots especially if not treated or if we burst pimples or pick them. You'll need skin lightening creams for a specified duration to reduce the marks , and this could also be dealt with chemical peeling. Also you must use a sunscreen to prevent darkening of the spots. For scars, creams may not work n you may need procedures like microneedling, microneedling rf, fractional lasers, prp or subscision or a combination of these. Send in your pictures if you need further assistance. Or see a qualified dermatologist near you and discuss the same with him. Hope this helps. Warm regards.
You can try for fractional laser for scars and or some depigmentation creams or lotions along with precautions to prevent blackheads. Also blackheads can be removed by some good dermatologist. U are most welcome at our clinic in janak puri if you desire so . We would be happy to help you with your problem. U can also visit website
www.drsuruchipurimakeovers.com if you want to know more about your query