trying to link original xbox

If I sort of get what you mean.

You want to link two X boxes together to play multi player games.

It will depend if a game has the option to create a server on one xbox where you can also jump in to play.

I`m not sure if the original Xbox supported system link display.
But I know the Xbox 360 does.

Each console is attached to its own tv.
And then a Ethernet cable is used to connect one machine to the other.

The cable must be what we call a cross over or X-over Ethernet cable.
You cannot use a normal Ethernet cable as they are wired diffirent.
You must have a copy of each game Disk you wish to play for both Xbox consoles.

And they must contain the same patches or update versions if needed. And the same revision of xbox dashboard.