You do know that you can setup port forwarding so that for example incoming port 8080 gets forwarded to port 80 on your PC running WAMPServer?
This would allow you to keep Apache on port 80 and do a test that proves you can actually get a response from an external browser using port 8080. If you then change the port forwarding so incoming port 80 gets forwarded to 80 on the Apache PC you would know that your ISP is blocking port 80.
If you still get no response using incoming 8080 to 80 on Apache PC then you will know port 80 is not being blocked by your ISP.
Also remember that you will have to configure your FireWall to allow incoming port 80 and/or 8080.
Also remember to test your extenal access from outside your internal network, as most home routers do not have the ability to spot that you are using the WAN IP address from inside your internal network and turn the request around and deliver it back into your network.
I have to add this as well. WAMPServer i.e. Apache on a windows desktop is not easy to make secure, and not recommended as a live web server environment.
---------------------------------------------------------------------------------------------
(Windows 10 Pro 64bit) (Wampserver 3.3.4 64bit) Aestan Tray Menu 3.2.5.4
<Apache versions MULTIPE> <PHP versions MULTIPLE> <MySQL Versions MULTIPLE>
<MariaDB versions MULTIPLE> <phpMyAdmin versions MULTIPLE> <MySQL Workbench 8.0.23>Read The Manuals Apache --
MySQL --
PHP --
phpMyAdminGet your Apache/MySQL/mariaDB/PHP ADDONs here from the
WAMPServer alternate Repo-X-X-X-
Backup your databases regularly Here is How dont regret it later! Yes even when developing -X-X-X-