Placing png files into doc.

The colours of the original photo are completely changed. Any help, please?

The color is changing because of the transparency, the same will happen if you place a PSD with transparency.

If there is any transparent object on your spread, the Transparency Blend Space affects the page preview (see Edit>Transparency Blend Space). You have yours set to Document CMYK, so you PNG gets previewed in your document‘s assigned CMYK space. It’s just the preview, the RGB color is not actually converted, but you are seeing what will happen to the color when it is eventually converted to CMYK for output

I agree with everyone that the preferred workflow would be to place the Photoshop files into your InDesign files.

In reference to your original question I'm guessing that this may be a result of color profiles or their absence. You may, for example, be using Adobe RGB 1998 as your color profile within Photoshop. When you export out your PNGs you may not be embedding that color profile (also assuming image not automatically converted to sRGB). When you place the PNGs into InDesign and in the absence of embedded profiles, the images may be displayed with an assumed color profile such as sRGB which would explain the color shifts.