At first, select oData service you want to check, for example, something with business partner.
Here is API_BUSINESS_PARTNER service - need to activate in /IWFND/MAINT_SERVICE
Then, go to "Call Browser" button:
URL with this format will be opened:
https://s4host.net:8070/sap/opu/odata/sap/API_BUSINESS_PARTNER/?$format=xml
Here you can see some collections, which starts from "A_" patterns:
Copy such collection (A_BusinessPartner) and put it after basic service name:
https://s4host.net:8070/sap/opu/odata/sap/API_BUSINESS_PARTNER/A_BusinessPartner
It brings the list of business partners from the system:
To have information about exact BP, put BP number in such format to URL:
https://s4host.net:8070/sap/opu/odata/sap/API_BUSINESS_PARTNER/A_BusinessPartner('300000')
You can do the same from Postman for example:
To expand business partner data for some particular directions, you can add such extension (in blue):
https://s4host.net:8070/sap/opu/odata/sap/API_BUSINESS_PARTNER/A_BusinessPartner('300000')/to_BusinessPartnerAddress
How to find an API on SAP S/4HANA OP (EN) | SAP Blogs
Create Sales Order - SAP Help Portal
https://help.sap.com/docs/SAP_S4HANA_ON-PREMISE/1dad2180e6f34b75ac77afce5cb5eda1/7ab0bcc20b1611da1503000bcddc2565.html?&version=2020.001
Other API-s examples
API_VMSVEHICLE
API_VMSVEHICLELOCATION
Operations for Vehicle Management System for Vehicle - Read - SAP Help Portal
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