Where can I view how Booking.com breaks down their payment

I'm very new to Booking.com
I've been trying to find, read or find out how the payment is broken down, meaning what the fee that booking.com charges?
When there is a booking, why doesn't Booking.com send you an email notifying you? AND letting you know how the guest is being charged and when?

I have had to bookings and NO email!

Thanks for any help.