Can my software send data to my site and read data?

Can my software send information to my site and read information off my site?

Imagine that someone opens a copy of my software. The IP address of that device send to my site. So I can see if that person is a friend or not. If that person is not a friend, I will set a variable to false. The software will then read it as false then the software will close out.

Is this possible to do? If so, how can I do this?