Hello Manjunath,
there should be no such transaction code for you to display the input parameters for the documents generated through TPM18.
You can check the posting journal via tcode TPM20 with Business Trans. Cat. 9000 and relevant posting data FI to find the relevant postings for derived business transactions.
Please save a variant before you execute TPM18, then you can check the input parameters afterwards.
Best regards,
Jasmine