I see you are new here on Hive. Generally it is a good practice when utilizing another individuals image to provide a source credit, even if the image is in the public domain.
https://phoneky.com/wallpapers/?id=w15w526985 just one of the many sites I found the image on. It also does not attribute who the author/creator of this image was, which is a shame as I would have liked to see more of his work.
he makes a valid point : /