As pointed out that sky is too washed out. It could be darkened to create contrast.
Here is a quick way to do this. First, create a duplicate layer by dragging the background layer into the New Layer icon. (Or go to Layer at the top of the screen and select Duplicate Layer.
Now, in the Layer box area where it reads "Normal" click on the arrow to get the select box and choose Multiple. Your image should suddenly be mostly dark. Select a large soft paint brush and overlay and a percentage of opacity starting with a bit less than 100, but over 50. Now just paint over all but the sky with the brush to lighten all but the sky.
It is probably best to get used to using the sliders in Camera Raw. Try white balance options first, and also try Camera Calibration. Try the choices under Camera profile like "camera vivid".
To darken the sky goto a minus number with the brightness slider, then increase the Fill Light to get the land mass brighter again. You can also drag the exposure button to the right and then increase the blacks to get back contrast and so it goes. Check the histogram. Your goal is to get both the triangles black. If the right one stays white, click on it and you should be able to see where the highlighted problems are as they will be blinking red in your image.
Fiddle and diddle until you get an image that pleases you. You can do a lot in Camera Raw. Click on the icons and move sliders!
Someone mentioned using Smart Objects. Research "Double Processing" In short, that method takes one photo, makes two one with a darkened sky, the other with a correctly exposed foreground and combining the two.
PS Remember the this is a thread asking about post-processing methods, and not about the merits of post processing. Remember, too, that one of the best at post-processing and editing was his majesty, Ansel Adams.
IMO this is a very successful composition except for that sky. I keep a sky folder, just photos of different skies and clouds at different focal lengths and lighting at various times of day. I use them to replace blaah
skies in my images. I have moons, too, some with blue evening or morning skies sometimes with black. Never know when a photo might need a moon.