@Luci3964 The Sync option will not be highlighted until there is an attached calendar to sync with.
In Airbnb:
Go to pricing and availability
Scroll down to calendar sync
Choose export calendar to get the URL to copy to a calendar that is outside of AirBnB
Choose import calendar to add a calendar URL that you have obtained from an OTA that is not AirBnB (Travestart in your case).