The Get Info procedure is a way to set an icon to something different than is already there. The normal way to set an icon is to include the icon file in the Resources folder of the application bundle and edit the name in the Info.plist CFBundleIconFile entry. If using Xcode, it has various options to generate and include the icon as part of the build process.
Topic:
Code Signing
SubTopic:
Notarization
Tags: