Find your Facebook Business ID
The Facebook Business ID is required information for the application for Official WhatsApp Business API.
Your Facebook Business ID corresponds to your Business Manager. You need this ID when you submit an application for WhatsApp Official Business API.
You need to log in to your Facebook account or contact the Facebook page admin for this setting.
Then select the Facebook Business that you wish to apply for WhatsApp Business API.
Scroll to the bottom on the left sidebar, select Business Info.
Facebook Business Manager
You will be able to locate the Facebook Business Manager ID on the top.
Copy the ID to complete the application for Official WhatsApp Business API.