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 peels, microneedling, microneedling rf, fractional lasers, prp or subscision or a combination of these. Yes, the procedures advised are safe. Warm regards, Dr Govind Suresh Mittal.