The HP Recovery Manager that would allow you to run a factory image recovery would be in one of two places.

The first place is on the hard disk and can usually be accessed from the startup menu. Press the power button and immediately tap the Esc key. That should invoke a startup menu. One of the Startup menu choices should be F11 (System Recovery)

The second place is on the USB Recovery media that you should have created by now. The most highly recommended type of media is a USB flash drive, not recordable media (DVD media). You can boot from the media when it is plugged into a USB port and access the HP Recovery Manager.
If you did not create recovery media and cannot access the System Recovery from the Startup menu, then contacting HP and ordering recovery media is likely to be your best option.