how to configure and consume Sharepoint online api from ECC6

Dear,

I've a requirement to call retrieve data from a list in sharepoint online and then update the checking result back to the sharepoint list after validating the records based on the logics and configurations in ECC.

Appreciate if the experts here can provide some step by step guide on what configurations are to be done and some sample codes on how to consume the api can be provided.

Thanks a lot in advance,

Francis