Zooming in to between 100%-200% is where the technical issues become noticeable. I'm spotting noise/artifacts, and halos around the top edge of the mountain and the dock railings. The image would benefit with some sharpening.
Hope that helps!
The sky has color noise and the horizon is not level.
Taken with a smartphone right?
The image quality on smartphones generally isn't so good when enlarged. Great for small screens/social media etc, but not so good for stock usage; especially when they might need to be printed to a large size!
When enlarged you begin to size noise and compression artifacts.
Have a read of these help guides:
Along with what the others have said about the technical issues, there is a very high probability that you would require a model release for the child sitting on the dock. If the noise and sharpness were cleaned up, the child would become even more recognisable.