Hi Nancy
From "Host"
Go to "Manage Listing"
click "Calendar and More"
Use the scroll bar on the left to scroll down
You'll then see "Photos"
Click and you will see "Add Photos"
Assuming you're photos are on your computer then you should be able to add them easily.
However, that's where I now need help......
I've got many photos already on my listing and I know how to move them around etc, but someone recently set my computer up differently and so my photos are now on photos.google.com - so can anyone advise how to get them from google onto my laptop so that I can use them in Airbnb?