I can see that you have the anatomy and proportions in manga style down pretty well.
Her outfit looks nice but there are missing some folds in the cloth e.g. where her arm is bend. (Here is a tutorial for reference: fav.me/d45ti5t)
I realy like the detail in her hair, by the way.
I can see that you did a bit shading here but it is too weak to tell the light direction and needs a bit more contrast.
The simple background makes you focus on the character more which is good.
I am a bit confused about the sky though. It's too blurry to be clounds and the skys color is too bright for it to be fog...
Good job on pose and expression, by the way.