Android Beta Secondary Display - How do I control it?

I'm enrolled in the Android Beta program with a Pixel 9 Pro Fold and I now have the "Enable freeform windows on secondary display", which I turned on. Now when I connect a monitor, it shows a full android desktop! However, I cannot find a way to control anything on this monitor, or "send" any apps over to it to be full screen. Is there any way to do this on android without connecting a bluetooth mouse and keyboard? With Samsung DeX, a little icon would show up on the bottom left of the phone and would turn the entire phone into a trackpad for the secondary screen. Thank you for any assistance, I really hope Android 15 delivers with this desktop mode....