This will not be a removal. It will be a combination of adjustments. Try to make a selection of ONLY the affected area - it won't be easy, since the edge softness looks like it varies (you can always adjust your layer mask later). Since it seems you're not that familiar with adjustments (from the nature of the question), I'd start trying to get the contrast close using a Levels Adjustment layer. Your selection will become a layer mask, so you'll only be affecting the inside of the selection. Then, for color, I'd likely be using a curves adjustment layer (if you're more advanced, you'll do better doing it all with curve adjustments). The full answer to this would be VERY lengthy (several chapters of a book) to get this right, but take a look at Adobe's videos (https://edex.adobe.com/browse?sort=Featured&r=resources) to learn about making selections, layer masks, and the Levels and Curves Adjustment Layers. One good thing - once you fix this, you'll have learned quite a bit!