To get the F4 help(from internal table) in selection screen

CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST'
    EXPORTING
      retfield               = 'SIGN'
*          PVALKEY                = ' '
     dynpprog               = sy-cprog"' '
     dynpnr                 = sy-dynnr"' '
     dynprofield            = 'SIGN'"'GDT_ZSTPOBJS-FIELDNAME'
**          STEPL                  = 0
*          WINDOW_TITLE           =
*          VALUE                  = ' '
     value_org              = 'S'
*          MULTIPLE_CHOICE        = ' '
*          DISPLAY                = ' '
*          CALLBACK_PROGRAM       = ' '
*          CALLBACK_FORM          = ' '
*          MARK_TAB               =
*        IMPORTING
*          USER_RESET             =
    TABLES
      value_tab              = gdt_t_sign
*          FIELD_TAB              =
     return_tab             = it_return
*          DYNPFLD_MAPPING        =
   EXCEPTIONS
     parameter_error        = 1
     no_values_found        = 2
     OTHERS                 = 3

  IF sy-subrc <> 0.
* MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*         WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
  ENDIF.