1. Create the BAPI Structure:

->Open Transaction Code: SE11

->Select Data Type and enter a name for your structure.

->Click Create and choose Structure.

->Define the fields for your structure, with the relevant business fields, including a primary key (if applicable).

->Save and activate the structure.

2. Create the Function Module:

->Open Transaction Code: SE37

->Create a new function module and assign it to a function group (if one doesn’t exist, create a function group using SE80).

->In the Attributes tab, mark the function module as Remote-Enabled (set to RFC).

->Define Import, Export, and Table parameters as required.

->Write the necessary ABAP code to implement the business logic in the Source Code

->Save and activate the function module.

3. Create the Business Object:

->Open Transaction Code: SWO1

->Create a new Business Object and assign it a name.

->Under the Methods tab, add the function module as a method to the business object.

->Define the method’s attributes and parameters based on the function module.

->Save and activate the business object.

4. Release the BAPI:

->In SWO1, change the status of the business object to Implemented.

->In SWO1, mark the business object and its methods as Released to make the BAPI accessible externally.

5. Test the BAPI:

->Open Transaction Code: SE37 (not SWUD) to test the function module independently by providing the input parameters.

->You can also test the BAPI in the BAPI Explorer (BAPI transaction), which lists all available and released BAPIs.