Acne scars

So for a few years now I’ve had so much acne of my back and butt and it really makes me feel so depressed and just super insecure. My boyfriend is thankfully so understanding and loves me anyway which im grateful. I truly feel this happened because of my diet. I eat so much crap that my skin is just at its worst! Has anyone went through this and did anything for it to look clearer. I really want to eat healthy i just hope that it does help heal my horrible skin. It just looks terrible you guys sos. Any lotions or tips? Id really appreciate any advice thanks!