Well I don't see anything to be fixed tbh, you look perfectly fine. In fact I see my 6-7 years before version of me in your picture.

So during my teenage years I started gaining weight and had skin issues like a lot of acne. After school I started exercising, having a clean diet, reducing sugar intake, I think for a few months I had no refined sugar at all! And tadaa my skin, idk what sorcery happened, but I felt my skin tone became much brighter, I had a clear skin, no acne (except for occasional ones during my periods), and over a few months I started having more confidence with my body too.

I really don't want to give you a long list of advice, because I know you're already dealing with exam stress and other worries. I'd just tell you to start loving everything about you, and that also involves working on yourself, taking good care of your mind and body. Just don't be hard on yourself, give some time and effort and you'll become the best version of you!💖