an API Management Platform, a service designed for API Management, which is the process of creating, securing, publishing, and monitoring APIs. Using this service, an organization can reduce technical complexity, quickly market solutions internally and externally, create and manage teams of API consumers, and improve API governance and security. These tools have been found to bring tangible benefits to businesses.
for the decoupling layer i found this link that explains it. sorry but these two topics are new for me too
https://mia-platform.eu/blog/digital-decoupling-layer/#:~:text=The%20creation%20of%20a%20digital,ord....