How to do this Count Connected Users on my Web Publish page (below) & how to import this on my WP Page(including login, inside layout)?
Then you need to use a plugin like Base Elements to ask a FileMaker Server question using Commando Line and and save the result to your solution.
Functions – BaseElements Plugin Help Centre
How to apply this plugin? I'm newbie for plugins!
You need to have FileMaker Server. Then install the Base Elements plugin on your server. You can read how to do that in the FileMaker Server Guide
Then you can use all functionality that was in the function list that I sent before.
To use a Commando Line call to ask FileMaker Server to see how many users you have connected right now. Here is a good article on what you can do from Commando Line
FileMaker Server: Don't Fear the Command Line
Retrieving data ...