There are 2 ways to connect with Booking.com: by exporting your listings to Booking.com if you don´t have them created yet or by mapping your existing Booking.com properties with Hostaway listing ID.
For more information please check here:
When you use the export option, we export Hostaway listing with all the content information to Booking.com. If you want to do some changes after, you have to do it directly on Booking.com as it is only a one time export. Further, all listings should only be in English Language and based on the market, location, the guests that come, you can translate it into other languages after the export is completed.
If you have your listings mapped with Booking.com properties and want to change some content related settings (photos, descriptions, contact info, taxes), you have to do it directly on Booking.com.