PR4100 Plex Media Server Issues

I can’t seem to get this plex media server running to add my media to plex. I login to my PR4100 and go to the app, click on configure

Then it tasks me with logging in, and takes me to the plex main page. When I click on your media it asks me to download plex media server. I’m stuck in a circle here.

If anyone knows how to resolve this issue please advise and thanks.