WhatsApp For PC is not available anymore because the official website is not working anymore. A good way to have WhatsApp installed in your computer is through Bluestacks. Bluestacks is a virtual Android emulator which allows you to install Android apps on your computer. The application is free to use. Download and install it, then access the built-in store and search for "WhatsApp". You might need to have a phone nearby to confirm the installation.
