Looking for a chatbot-creation guide.

I have noticed a lot of recent press around the “Talk to Jesus” chatbot(s) on certain websites, where the bots’ responses to user queries are basically conditioned on “What would Jesus say?”
I’m not looking to do a religious chatbot, but I would like to know (in layman’s terms) what are the steps, costs and options for creating and deploying a chatbot that will similarly represent a certain POV and tone, etc. in its answers to user queries. (I would like to do so cheaply if possible.)
Any advice or assistance would be appreciated, thanks!