Whonix-Workstation ™ Overview
Whonix-Workstation ™ is software. After installation of Whonix ™, Whonix-Workstation ™ will be connected to Whonix-Gateway. The latter runs Tor processes and acts as a gateway, while the former runs user applications on a completely isolated network.
Whonix-Workstation ™ is the place where all user applications like Tor Browser should be launched. This also ensures applications will utilize the Tor network because only Tor connections are permitted.
Whonix ™ also provides stream isolation for many pre-installed or custom-installed applications when they are used simultaneously in Whonix-Workstation ™. For example, Tor Browser, Hexchat, Thunderbird and several other applications use a dedicated Tor SocksPort, preventing identity (pseudonym) correlation that may otherwise occur when the same Tor circuit and exit relay are used.
Whonix-Workstation ™ is already pre-configured for use with Whonix-Gateway.
For a functional network connection, Whonix-Workstation ™ requires a running Whonix-Gateway. It is therefore recommended to first start Whonix-Gateway before Whonix-Workstation ™.
But it is also okay if the startup sequence is reversed. If Whonix-Gateway is off, Whonix-Workstation ™ can only be used offline. Even without a running Whonix-Gateway there is no way Whonix-Workstation ™ could connect to the clearnet internet. In other words, Whonix ™ is fail-safe.  Whonix-Workstation ™ will either use Tor network or have no network connectivity at all.