Hi there!
Sounds like an interesting use case, curious to your work!
Rasa has a couple of useful resources to get started (with developing, or understanding the basics of Natural Language Processing).
From the top of my head I would refer you to their Youtube channel , it has some great content.
This one in particular can be useful to get started: Rasa Livecoding: Create a new assistant in Rasa 2.0 - YouTube .
You can always follow their certification course, it’s on Udemy (and due to all the “promotions” of Udemy, at a fairly low cost 
).
Although there were some major updates, I believe after you get the hang of the Rasa framework, it is still possible to follow some “older resources”. If you really want to follow along a bot project build from the ground up (and catch some best practices on the way), I would recommend the Breakout Bot series. Note, Breakout Bot is updated to Rasa 2.x in season 4