Not that it has anything to do with Android (unless you're trying to install Android on a PC), but it means what it says - that your computer doesn't support hardware accelerated virtualization, and evidently you have your virtual machine software (VirtualBox?) set to run hardware accelerated virtualization, or you're trying to run Android-86, which also uses it. In other words, "you can't do that on this computer".
Either turn off hardware accelerated virtualization (if you're running virtualization software) or get a computer with a CPU that supports it. Read
this page, at the "Dependencies and prerequisites" area ("Configure Hardware Acceleration" section in the left column, then scroll down just over a page [if you're on a PC]).