Yes. The host OS, in this case Unraid, boots directly onto your hardware and does not depend on your VMs. Once booted up, it will automatically (if checked to do so) start your VMs up, which can then be accessed however you see fit. Unraid continues to operate as normal whether the VMs are running or not.
Your VMs on the other hand do rely on unraid running. So if you stop the array, any VMs hosted on that array will stop. The VMs also cannot run if the host OS (unraid) doesnt start.