How to retrieve Facebook Access Token

Create an app in https://developers.facebook.com/apps/

Choose other

Choose type as business

Name the app and click create

Add products marketing api and facebook login for business

Go to Settings → Basic and retrieve the appid and secret

Go to Tools → Graph api explorer

Select your app and add the permissions needed. Click Generate token

Copy the token and create a Long lived Access Token Get Long-Lived Tokens - Facebook Login - Documentation - Meta for Developers