Hi @Heather188
You don't need to send them anything.
They don't have a booking.
Just tell them, they didn't book and if they are interested in your place to send you a booking request and you are happy to consider their booking.
They just need to do what any other guest would do. Put in the dates, number of people and if they have the payment set up they can send you a request. Simple.
Don't communicate with them off Airbnb keep everything on the platform so there is a record. (how did you share contact details by the way)
A word of warning, sometimes people try and scam newer hosts by tryng to book off platform.