hey, i just started a small Dueling server and i uploaded the duelers mod into it, how do I execute it though and load the mod into the server?

Edit: this is JKA btw, not JKO

You can't. The server has to be restarted to that mod from the command line.

what do i put in the cfg to do it then?

I don't know the exact syntax so I'll let someone else chime in here but it doesn't go in a cfg. The server would have to be running to read a cfg and the MOD execution needs to go in the line that STARTS up the server.

On linux would be something like this:

./linuxjampded +set dedicated 1 +set fs_game YOURMOD +exec server.cfg