You can change the PF Keys that you have defined by using one of the first three choices on the Function Keys pull-down. Choosing "Non-keylist PF Key settings" calls the PF Key Definitions and Labels panel, where you can assign PF keys to ISPF commands, and label them. This choice is like using the KEYS command.

Choosing "Keylist settings" from the pull-down is like using the KEYLIST command, and the "Tailor Function Key Display" choice calls up the Tailor Function Key Definition Display panel.