Regarding black marks due to pimples.

Greetings. Pimples may often leave spots especially if not treated or if we burst pimples or pick them. Reduce intake of milk, milk products and junk food. Wash your face regularly with a salicylic acid based grace wash. You'll need topical or oral retinoids depending on severity of the lesions.  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. Discuss these options with a qualified dermatologist  near you in detail. (Caution: do not be lured by unrealistic claims and offers made by quacks who claim to be specialists in trichology n cosmetic sciences or even saloons. Make sure u are treated by a qualified dermatologist). Warm regards,  Dr Govind Suresh Mittal, Bengaluru .