Verbesserung?

It’s not bad for the beginning. But please, please don’t shave “Airbrush”. These mistakes make most of those who start with Digital Art. And never use black as a shade color, but only a darker shade. Zb. did you use light green for the skin, so you best use dark green as shade.

I would also advise you to first draw a lineart consisting of clear lines. Because now with your picture the problem is that especially the lower area of the head looks very blurred and dirty. When you first draw a lineart, the whole works much clearer.

I would also advise you to make the lineart only with a single pin type. Only when it comes to texture should you use different pens.

After the lineart, I would then paint the image in its basecolours (the basic colors) and finally add textures, shades, lightnings etc.

In addition, the hair looks a little matte. Hair has this gloss effect. You should practice that.

Hope I could give you some tips.