You are using Oracle VirtualBox on a Windows host. You are using a Linux guest that is running Apache web server. The Apache httpd service is running on the guest Linux server. But when you are on the Windows host, you try to access the website, you get an error in the web browser. This is the error you receive:
"This address is restricted
This address uses a network port which is normally used for purposes other than Web browsing. Firefox has canceled the request for your protection."
What do you do to view the web page running on the Linux guest when you are on the Windows host?
Go to the back end. Specifically go to the Oracle VirtualBox window for the server with the Apache service. Go to Devices -> Network -> Network Settings -> Advanced -> Port Forwarding.
Make sure that there is a rule that involves guest port 80 (or whatever non-standard port Apache web server is configured to use on the guest) and host port 80. If you do not use host port 80 in your "Port Forwarding Rules", Firefox and Chrome will restrict the address.