Ok So Here's The Thing.. Ever Since I Could Remember

Ok so here's the thing.. Ever since I could remember my vulva and area around it (on the legs) and butt crack are like 3-4 shades darker than the rest of my body and as a teen who is thinking consciously about what if when I decide to have sex, whether it'll turn the guy off.... How do you recommend I lighten these areas in a natural way without having to use damaging chemicals on my body??