The VDI desktop system can be restarted with the "contextual menu" in the VmWare Horizon Client. This may be required, for example, if the desktop became unresponsive. The "Restart" option will produce a "soft" reset, switching off the operating system and the "Reset" will produce a "hard" reset, equivalent to using the "off" button of a computer. The first one should be tried first, the second one only as an alternative if the "soft" reset didn't have any effect after waiting a few seconds.
The contextual menu can be invoked using a right-click or, when using a MacBook, click with two fingers in the touch pad.
If you can't see this window, you may have an automatic login setting enabled. In this case, go to the contextual menu (if in full-screen mode, move the mouse pointer to the top of the screen and wait until a top bar menu shows up). Then go to "Window" and select the "VMware Horizon Client" option at the bottom.
If there is not a "VMware Horizon Client" option at the bottom, go to "Connection" instead of "Window" and select "Log Off" from the menu, so you can see the desktop selection screen and go to the next step:
While there are also "shutdown" and "restart" options from the desktop itself, these require "root" access at this time, so they won't be accessible to users:
However, if you click the power button, then select your user account name and then "Log Out" from the drop-down menu, your session will be closed and the system will be automatically rebooted afterwards, so you will achieve the same result.