Use on a Netgear UTM9s

Can OpenWRT be used or created for a Netgear UTM9s.

No, the device is not supported. You can start to investigate if it is actually possible to add support for the device by following the guides here:

If this is something you'd like to see happen (and assuming it is possible to support), you'll likely need to take a lead role in the development process since you (presumably) have a device in your possession.