Start with the Dialog Developer's Guide and Reference in ch.2.13, "ISPF Services in Batch Mode".
If the process is one that you (in fact) can run in the background, your JCL must allocate all the necessary ISPF filenames: ISPLOG, ISPPROF, ISPPLIB, ISPSLIB, ISPMLIB, ISPTLIB... possibly others, too, depending on the actual process. You must then start execution by "ISPSTART CMD(...)" in SYSTSIN.