If you're looking to apply for WhatsApp Business API, then need an approved Facebook Business Manager account.
This is important because, without an approved Facebook Business Manager account, you can't get complete access to WhatsApp Business API. You'll only be able to send messages to 250 users in one go.
Meanwhile, with an approved Facebook Business Manager account, you can message Unlimited users in one go by upgrading your Broadcast tier.
For all this, you need to first have a Facebook Business Manager account.
In this tutorial, we'll tell you how to create a Facebook Business Manager account.
So, let's get started.