Ensure the right-click functionality is enabled in your settings or preferences.
Kali is running inside VirtualBox on a Mac with Sierra, yet you can't perform Ctrl+Click or right-click.
Do you want to add extra guests? It seems unusual at first.
Check if it's a MacBook Pro. If it is, use two fingers on the bottom-right corner of the touchpad for a right-click.
Appreciate the help! I gave it a try and it functioned properly.