Not until you tell us the rules for what you're trying to do which are not obvious from your example. Are you trying to insert the first record from input file 1 after the first record from input file 2, or is it something more complicated than that based on the "keys" of the records, or something else?
Can input file1 only have one record?
You need to give a complete description and example of what you're trying to do and the possible variations. Then somebody can help you.
Also, give the RECFM and LRECL of the input files and the starting position, length and format of all relevant fields.