Joined: 30 Nov 2013 Posts: 516 Location: The Universe
TPX is a product - I presume you are referring to CA-TPX, a session manager product marketed by CA Technologies, or whatever their name is this week. You are really asking how to create a screen for ISPF, a TSO application product written by IBM.
ISPF screen skeletons are in a PDS data set specified by the ISPPLIB DD statement in your TSO session. The actual data sets vary by installation; you will have to find out their names yourself. The member name for the ISPF Primary Options Menu may be ISR@PRIM, but yours may be different.
There are several manuals describing the ISPF product. Find them and read them.