[Not a question] Sending data over the internet using WCF between computers

See more:

C#

WCF

I have been trying for a few days to get something working but have had no success so I have got to the the point where I want to ask someone directly. I am trying to make an application that has a central server/responder on a computer that has the data I need and a client on another computer that will send a code over to the server which will then be deciphered by the server which will then send the required data back to the client. There will be multiple clients accessing the one server and it only needs to send quite small strings (the longest probably being image data)

ClientA ------------01005------------/Server\
ClientB ------------01003----------- | Server |- Return to whichever client sent request
ClientC ------------03007----------- \Server/

Each 'user' will have an ID that is sent in the request which will be formed like this:

<user[code]>
<CodeProject[01005]>

Could someone please write me a bit of code using WCF to help me accomplish this? All it needs to do is have a client that can be used multiple times and a single server as a console application. Simple back and forth strings basically. I know it is a bit of a big ask but I can't find anything that will work. Thank you so much!