I’m no expert, and I don’t know if that’s exactly the answer you want, but I’ll give you some tips on what I’ve seen.
First in robots.txt
from your site disable the directories so that they do not appear in search engines, see the example: (the name of the directories will depend on what you have at the root)
User-agent: *
Disallow: /administrator/
Disallow: /administrator
Disallow: /cache/
Disallow: /cli/
Disallow: /components/
Disallow: /images/
Disallow: /includes/
Disallow: /installation/
Disallow: /language/
Disallow: /libraries/
Disallow: /logs/
Disallow: /media/
Disallow: /modules/
Disallow: /plugins/
Disallow: /templates/
Disallow: /tmp/
Then create a file index.html blank at the root of each of these directories, so if someone tries to enter straight through the folder path will fall on a blank page...
<!DOCTYPE html>
<html lang="en">
<head>
<title>Document</title>
</head>
<body></body>
</html>
And lastly, try to "mask" that vc is using Wordpress, remove or rename the codes you have written Wordpress, for example to <meta name="generator" content="WordPress.com" />
in the contente
put your company name.