Hello @Sally250,
On airbnb the guest doesn't pay the host. When you make a reservation and the host accepts it Airbnb charges the card that you have registered in the payments section of your account. So you pay Airbnb.
You are usually charged in full at the time of making the reservation unless your reservation is for 28 days or more or Airbnb offered you, and you selected, the pay less upfront option.
If the reservation is for 28 days or more you pay for the first month at reservation time and then monthly after you check in.
If you were offered, and chose, the pay less up front option then your card will be charged 50% at reservation time and the remainder a few days before check in. You cannot decide when to pay the second 50%. Airbnb decides that.
When am I charged for a reservation?
pay-less-upfront-terms
Steve.