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.
The OP should have done that before hiring employees if the OP made transactions via bitcoin. Because usually before recruiting employees we look for someone who has already mastered what we need to help us. But that's not a problem, now the OP just needs to slowly teach them to transact directly with bitcoin. For the time being, they just need to understand how to transact, because that's what they need quickly. In the future, the OP can teach more about bitcoin.