Admin TURN is one of the server administration windows. Open it from File > Admin; it opens as a desktop window you can drag, resize, minimize to the taskbar, and close with its title-bar X.
What it shows
Two read-only panes: relay statistics and the allocations currently held. If no TURN relay is configured the stats pane says so rather than showing zeros.
Snapshots, not a feed
The numbers are from the last time Refresh ran. Nothing here updates on its own.