When ever a customer desires to pay in Bitcoin/crypto in my absence, I am usually contacted by my employees. I have explained some few details on how to receive payment from customers in crypto but I think they still find that means of payment as not being convincing, so I want to take out time to teach them Bitcoin, advantage, users, how to receive and how to send Bitcoin.
Isn't it that if they are just processing payments, then you just need to teach them how to do it like how you teach them how to use POS? They do not need the nitty gritty details of bitcoin, just how to process the payment and what to do in case transactions get stuck. At least as an employee, that is just what they need to learn.
But of course, if you want them to have knowledge about bitcoin so that they can share it with your customers, then they should start with the basics of bitcoin: transactions, fees, confirmation time, mining, etc.