It might be different for you having come from the predecessor, but I found it quite hard to get started with the App Platform. There is a conflict between DO's attempt to have a web interface that allows you to create and manage apps, and the underlying YAML/Buildpacks that actually model your apps. While the web interface is OK for seeing your apps at-a-glance, it's definitely not OK for creating and configuring new apps. For that you need to use the YAML config files and probably doctl (their CLI app). It took me a long time to understand this. Their docs don't do a good job at explaining the App Platform at a high-level. That said, I've still found it very useful for "simple" webapps.