STEP 2: Create a business app
Go to developers.facebook.com/apps and create a new Business app, which will generate your Meta app ID. If you are signed into your Meta Business Suite account, the app creation flow will present you with a list of existing business portfolios you have already created, or have been added to.
If you are not presented with a list of businesses, go to business.facebook.com and sign into your Meta Business Suite account, then reload developers.facebook.com/apps.
Select your business portfolio and continue. In the next screen, select Other, then Business app, and add an app name and your email address. Be sure to select your business portfolio in the Business portfolio dropdown menu before creating your app.