Since your legs are thin and your thighs are thick, it is very appropriate to wear a skirt, which will not expose the shortcomings of your thighs, but will expose your slender legs to look better.

Don't pay too much attention to the scar on your leg if it is not obvious. After all, no one is perfect, and others will not care too much. If it's obvious, you can only wear socks, hehe (otherwise try using scar-removing products, and the effect is not great! Fortunately, it's almost autumn, so it won't be too hot to wear socks. If you are conservative, wear dark or monochrome stockings. If you don't want to be too rigid, it is recommended to wear colored stockings, stripes or other socks, and a pair of small round shoes, which will definitely look good.

There is another way. If you are not fat and your upper body is thin, you can turn your attention to your upper body. Your coat must be a school uniform, too. Bring some trinkets, lovely or bright necklaces, brooches and scarves. But you are at school, I wonder if the school can let you dress like this, hehe!

Just a personal suggestion, I hope you are more and more beautiful! Also, self-confidence is more important than anything else, even the scars on your body can't hide your self-confidence light!