how to run jabascript inside php code example

Example 1: run php server

cd path/to/your/app
php -S localhost:8000

Example 2: how to run php inside js

You can't run PHP with javascript. JavaScript is a client 
side technology (runs in the users browser) and PHP is a 
server side technology (run on the server). If you want to 
do this you have to make an ajax request to a PHP script and 
have that return the results you are looking for.