How do I get rid of scars from former back acne and prevent it from coming back?

2 years ago, I got minor out of control back acne that has finally cleared up to a manageable few tiny pimples a few months ago. I am very happy but the only problem is that the minor breakout left many many scars across my back.

How do I get rid of the scars? Is this possible?

Also, How to I prevent the pimples on my back from coming back?

Thank you for everyone who answered.

I am 13 and goes to the beach often in a bikini with my back shown. I’m really self concious about the scars and pimples.