How to change png to ICO?

I'm curious about the process of converting PNG images to ICO files. Could you please explain the steps involved in detail? I understand that ICO files are specifically used for icons in Windows applications and that PNGs are more commonly used for web graphics. However, I have a need to convert some PNGs into ICO format for a project I'm working on. Are there any specific software tools or online converters that you recommend? Additionally, is it possible to maintain the quality of the image during the conversion process, or are there any common pitfalls or challenges I should be aware of? Your insights would be greatly appreciated.