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Facebook Business Account: Meta Business Manager is a tool that helps you organise and manage your business. You can create your business manager by following this guide Create your a Business Manager
Facebook app: The Facebook app contains settings for your Whatsapp WhatsApp experience. To create a new app, visit the app dashboard by clicking "My Apps" in the top bar of the developer page.
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Before you begin, make sure that you have met all the requirements listed above.
Add the Whatsapp WhatsApp platform to your Facebook app
In the app's settings sidebar under "PRODUCTS", click "+ Add Product".
Hover over "WhatsappWhatsApp" to see the options.
Click the "Set up" button. The Whatsapp WhatsApp platform will be added to your app and the Whatsapp WhatsApp settings console will appear.
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Configuration
Under the section WhatsApp, select the “Getting started” option and go to step 5 Add a phone number to start sending messages to any WhatsApp number.
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