First, TCP/IP configuration is not a topic for mainframe beginners and students. Only the site support group should be configuring TCP/IP since there are a number of options that require knowledge of how the site network is set up.
Second, everything you could possibly want to know about TCP/IP -- including configuration -- is in the manuals. Check the Communications Server bookshelf at the IBM web site for details of the IBM TCP/IP implementation.
Third, I know of at least two TCP/IP products for the mainframe -- one from IBM, one from CA. The specifics of configuration greatly depend upon which product is being used, and some of the commands for TCP/IP vary between products. Unless you know for sure which is used at your site, there's no way to answer to your question completely.