Sky Replacement
With Sky Replacement Photoshop automatically replaces the sky in your photo with another, including recoloring the foreground. The AI recognizes the sky, cuts it out neatly and adjusts the landscape's lighting to the new sky. That turns a dull white sky dramatic in seconds.
Choose Edit, Sky Replacement and pick a sky from the library or load your own. Play with the sliders for edge shift, brightness and color adjustment, so the transition and mood match. Photoshop delivers the result on separate layers with masks, so you can still adjust everything. Tip: pick a sky with the same light direction as your foreground, otherwise the eye instantly spots that it is off.
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The presets on this site set these adjustments up for you as a starting point, which you then fine-tune to taste.