So after searching for a while, and having to look here and there. I figured it out. No need to download any other calendars other than what you have on your iphone/ipad.
Simply put:
It is best to do this from a desktop computer.
Exporting:
From AirBnB, under Listing, select Availability. Scroll down to Sync Calendars and select Export Calendar. Copy the link.
Importing:
Go to settings on your Iphone/Ipad, Tap Passwords & Accounts, then Add Account. Select Other, go down to Add Subscribed Calendar. This is where you will paste the link (previously copied from exporting) into Server. Click next then Done.
You should now be able to go back to your Iphone/Ipad Calendar and view all your bookings.
Hope this helps!