ASTPP portal website index file modification help

Hello, I want to say that I’m coming from testing ASTPP Community for a few days and I really believe it’s a very nice billing program, but I wonder if someone can help me out with this one,

I want to add a web code to the head section of the index or php file for the portal website in order to add a live chat program for live support (#1 Messaging Platform For Startups & SMB's - Crisp) but I cant find the files to modify anywhere, supposedly the index files should be on /var/www/html/

Also I found the “astpp” and “fs” folders inside the “html” folder mentioned above, they contain an index.php and index.html files but they don’t seem to be the ones I’m looking for.

Anyone who knows where are this files or how can I modify them in order to add my live chat plugin?

Thanks @dannyltd
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