Do you just want to match the records just by the order they came in each file? record 1 from file 1 should be tagged with record 1 in file 2 and record 2 from file 1 should be tagged with record 2 in file 2 and so on?
What is the LRECL/RECFM of the input files and desired output file?
Answer these questions and we will show you a way to do it
MERGE can combine individual sorted input data sets into one sorted output data set. The question in this thread had nothing to do with that. It's about "joining" fields from two files. When the OP answers Kolusu's questions, we'll show how to do this.