Look for a way to remove shadow from png images

I don't think you can do this.

If the shadow is on a transparent background and you want to keep the icon/text intact, carefully selecting and removing the shadow area manually is often most effective.

If the shadow is a separate layer or element, simply delete or hide that layer. For simple shadows, sometimes color replacement or cloning tools can help remove or blend out the shadow. If the shadow is hard to select, manual retouching with a brush or clone stamp may be necessary.