This is a FreeNAS data disk and can not boot system. System halted.
The system BIOS will vary depending upon the motherboard. Accessing the BIOS also varies, and on my system I repeatedly tap the del key during the start up. Select the second option Advanced BIOS Features
The next screen shows the advanced features. Select Hard Disk Boot Priority
Ensure that the USB stick is top of the list of drives. Check out the help on the right side of the screen for the mechanism of doing this.
Save this and reboot the machine and you are back in business