Do you have any service listening on port 80? If not, I’d close it in the firewall and disable the forwarding in the router. Also sounds like a bad idea to set your router security to ‘low’, whatever that means for your router.
You can use a tool like this to check if your ports are accessible from the internet: https://www.yougetsignal.com/tools/open-ports/
So that means the router isn’t forwarding the ports to your devices. As others have said, it could be the ISP blocking it or it could be a configuration issue in the port fowarding.