

Right click on the PKG file and select Open with > WinRAR (or any other application you want to open the PKG file with).

Select Security & Privacy from the System Preferences window.
HOW TO OPEN PKG ON MAC INSTALL
You can use the following software to open and view the contents of a PKG file without installing it. PKG format is used by Apples OS X operating system and contains compressed files needed to install an application. Open System Preferences by clicking on the Apple icon and choosing that option. To do that, right click on the PKG file and select Show package content in the menu. Or, you can also view the content of the PKG file without installing the application.

If you want to install the application, double click on the PKG file, or right click on the PKG file and select Open with > Installer.app.
HOW TO OPEN PKG ON MAC MAC OS X
If you download an application for your Mac, the installation files may be stored in a PKG file. Uninstalling packages (.pkg files) on Mac OS X Edit Created, updated It used to be the case that you could install packages on Mac OS X by using lsbom to inspect the list of installed files recorded in the files under /Library/Receipts. An app that has been notarized by Apple indicates that Apple checked it for malicious software and none was detected. Statisically, these users are most likely running the Google Chrome internet browser. If your Mac is set to allow apps from the App Store and identified developers, the first time that you launch a new app, your Mac asks if you’re sure you want to open it. Visitor data analysis shows that these Apple MacOS Installer Package files are typically seen on Windows 10 user machines from Brazil. If you are unable to open it with a text editor, you may have another type of PKG file. The PKG file extension is a Apple MacOS Installer Package file developed originally by Open Source for RPCS3. Symbian PKG files can also be opened with a text editor since they contain command lines, instructions and information in the form of text. If it is in Symbian OS installation format, use a device with the Symbian OS installed to open it. PKG files which are intended to be used on Mac cannot be installed on any other operating system, though the content of the file can be viewed. In Mac, the PKG file is associated with the Installer tool that manages the installation of such files. If the PKG file is in Mac OS installation file format, use Mac OS to open and install the application. Various file types may use the PKG file extension such as the PlayStation Store Download Package, or the Symbian OS, which uses PKG file for storing application execution SIS files in the system in the form of text.
