To brighten it, click on:
Image > Adjustments > Brightness/Contrast
There you will find a slider to control your level of brightness. You can also go into 'Image > Adjustments > Levels' and mess with that slider, it has a little more control over your midtones if you slide that center triangle around.
Maybe also add a Sharpen filter to the layer that the character is on, she looks kinda blurry. To do that, select her layer and click 'Filter > Sharpen > Sharpen'. It might clean it up a little bit. If it's not sharp enough, you can sharpen it again and again.
Hope this helps ^^