The link above from Microsoft does a decent job of describing the new functionality from a 10,000 ft view, but what it doesn't describe is the more intricate features of this that will have your Credit and Collections team giddy with joy.
Over the next few weeks, I will be detailing new features that I demonstrated for the D365UG on June 17, 2020. You can access that recording on my company's website if you are interested: https://ellipsesolutions.com/a-quick-demo-of-dynamics-365-credit-management/
In order to get this functionality in your D365FO environment, you will need to go to the Feature management workspace and enable the Credit management feature. I recommend always trying new features in a sandbox environment to ensure everything works properly and as expected before enabling this in your production environment.
|Credit management is available as a new feature in the Feature management workspace.|