nLockTime transactions are really not intended to be used by individual users, and creating a nLockTime transaction does not appear in the documentation for the bitcoin core wallet.

If you are a business that sends many bitcoin transactions, there may be a use case for nLockTime transactions that makes sense. nLockTime transactions are really intended to be used for applications used "on top" of bitcoin, such as Lightning Network wallets, or Thunder wallets.

If you want to show your friends a "real world" nLockTime transaction, you can open a LN channel with yourself (or your friend), send some transactions between the LN nodes so that each node has a "settlement balance" of about half the channel value, and have one node unilaterally close the LN channel in which the other node does not corporate. This will allow you to show your friend nLockTime transactions in use, and will also allow you to highlight the security (and risks) of using LN.