First, you need to register as a meta developer, and then enable two-factor authentication for your account.
And then you can click the “create a new app” from the top right of your dashboard, and then select “Business” as the app type:
Then put the display name, and add the app contact email, if you want to connect this app to any of your business accounts, you can click the drop-down to connect them.
Then you need to click the “configuration” to set up your own webhook.