What's the difference between Cloud Foundry Environment & Neo Environment?

The main difference is that the Cloud Foundry Environment consists of an open-source runtime and the Neo Environment consists of SAP proprietary runtime. Additionally, the Cloud Foundry Environment supports Bring Your On Language concept while the Neo Environment does not.

Another difference in the environments is that Cloud Foundry supports multiple Data Centers, such as AWS, Azure and GCP, while Neo supports only the SAP Data Center.