There is a built-in alternative to the function keys.
You can use the sequence "Escape Key - Number Key".
This will let you navigate the different menus in SMIT while in a terminal emulation session from the CommandShell windows, Text based Console Window, Telnet session, and so on.
For example, from the CommandShell window, if you need to enter F4 (Function Key 4) to generate a list of options for a field, you can enter the sequence Esc 4 ( Escape key - Number 4 key ) and obtain the same result.