However, looking again, I guess only white/black/background find ㅜ ㅜ ㅜ ㅜ ㅜ
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Where the image is transparent it will look like a checkboard assuming there is no other layer below it covering up the checkerboard.
Transparent areas are not really selectable as there is nothing there to select.
However you can select the edge of your image then invert the selection. This could be useful if you need to fill, but it would be much quicker to create a new layer behind the image and fill the new layer. Then if needed you can merge the two layers.
But I am going way ahead of myself since I don't really know your intentions with the image.