Acne Scars on Teenager 🥺

Hii guys, so I kinda need a little help in choosing what products I should buy for my little sister. She is 15 years old and has suffered with acne since she's 11 and now got a lot of scars because of it. She didn't wanna do something about it before but now, she seems interested on what I applied on my skin and everything but our concern is different since I don't have scars like hers. Her skin type is oily and sensitive. Her concern right now are scars and mild acne. She only need a basic right now (cleanser, moisturizer, sunscreen). Any suggestions that could help her?