Dillon wants to start a podcast, but doesn't know how to build his audience. Leo says that's the wrong way to think about it. An "audience" expects to be amused and entertained. For podcasting, that's just not enough. He'll want to build a community who will stay engaged with him and his show. He'll want to have discussions, chats, etc. The realm of media has really changed.
So he should have social media, a website, and maybe even a chatroom. He should also make sure that the podcast is on a topic he's most excited about. Think about a very specific topic, too. He may have to do it for free for quite awhile until he builds it up.
If he can get someone older involved, he could try using Patreon.