How to block access to the site?

Question

Computer networks

There is a site. It is necessary to restrict access to a certain person so that he sees the blocking window (or whatever else is possible there). It is desirable that you can block access to VK, but if this does not work out, then give another way. All the most simple.

Answer 1

If the site is yours and the person has a guaranteed permanent IP for the rest of his life and you know it, then you can.

Answer 2

It is possible by IP via .htaccess

Order Allow,Deny
Allow from all
Deny from 192.168.1.1 #например

But this is if a person has a static IP and you know him. And while you have apache