I can not find that exact router model but it comes up with similar devices that are 4G. This means mobile broadband. In general if you get your internet via a cell phone tower you do not have a public IP and will never be able to port forward.
Even if this is not a mobile broadband connection you need to check that the IP assigned to your wan port is the same as sites like whatsmyip report. If they are different there a NAT router in the path and you likely do not have a public IP.