I'm 27 female.i had acne before and nowadays very less in no.but the scars/marks not going away.any simple method we can do by our own 2 remove them?

Unfortunately no: It sounds like you had/have cystic acne. With cystic acne the bacteria dissolve some of the fat under the skin causing the scars. A dermatologist can help.

Improve, not remove.: Scars cannot be removed but there is a large variety of techniques to improve their appearance, both surgical and non-surgical. Your acne should be well-controlled. See a dermatologist to begin your search for an appropriate course of action. Good luck!