Hi. Greetings. Pimples may often leave spots especially if not treated or if we burst 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 user a sunscreen to prevent darkening of the spots. If you have pits and 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 dermatologist near you and discuss the same with him. Sorry this forum does not permit me to prescribe medications without examining you. Hope this helps. Warm regards.