How to block any website with php

Answer 1

What do you mean?
you don't want to see any site 'developed with php' ?
or
you want to block a specific site using php ?

If it's an IP you want to block read
https://stackoverflow.com/questions/2869893/block-specific-ip-block-from-my-website-in-php

Answer 2

I want that a particular site will stop working if I learn php professionaly.is it possible?