Going into Endevor and found that the command line is at the bottom. Split my screen to check the ISPF setting and it shows this:
All supported releases
Go into Endevor and on the command line type Settings and hit enter.
The following screen will be displayed.
Notice that "Command line at bottom" is selected ... Remove the '/" - Hit Enter - then PF3 and now the Command-Line in Endevor is at the top.