The FreeBSD Foundation provides us a tutorial on getting FreeBSD setup on VirtualBox. VirtualBox is an open source virtualization platform available on Windows, OS X, and many other operating systems. Follow the link below for the full instructions.
freebsdvirtualbox

1. Installing VirtualBox

  • Visit the Oracle VirtualBox website, the download page can be found here: https://www.virtualbox.org/wiki/Downloads
  • Select the Binary that applies to your operating system and machine. VirtualBox is available on Windows, OS X, Linux hosts, and Solaris. The download links can be found under the first bullet-point as pictured.
  • Opening the downloaded package will start the installation walkthrough. Once it finishes, you’ll be able to launch the application.

2. Identifying Your Processor: ….

Full tutorial: https://www.freebsdfoundation.org/freebsd/how-to-guides/installing-freebsd-with-virtualbox/