You did not specify what you installed so here are a couple of assumptions. Apache server with PHP. Web files will be placed into the htdocs folder. Windows IIS with PHP. Web files will be placed in the wwwroot folder (I think). Using a text editor like notepad create this file.
<?php
phpinfo();
?>
Save it as test.php with notpad when saving using the dropdown box select All Files (NOT txt) either to the htdocs foler or the wwwroot folder depending on which server you have.
Open your browser and type http://localhost/test.php into the Address bar. You should see a long table full of information about your PHP install if not you either do not have the webserver installed or running or you do not have PHP properly installed. Let us know what happens. NOTE if when saving the test.php you do not select All files when saving it will save as test.php.txt and not work.
