Ensure the background of the PNG is transparent; otherwise, your character may appear with a solid white or black box around them in-game.
The file is an asset often associated with character customization in indie games or specific modding communities. Because it is a specific file name rather than a widely known brand, the "proper guide" for using it depends on which platform you are trying to apply it to. Common Use Cases skin-dw13.png
Providing that detail will help me give you the exact folder path or upload instructions. Ensure the background of the PNG is transparent;
Ensure the image is the correct size for your target game. For example, Minecraft skins must be exactly Common Use Cases Providing that detail will help
If you found this in a game's local files, it is likely a texture sheet for a 3D model. Opening it in an image editor (like Paint.net or GIMP) will show you the "unwrapped" skin of the character.