A simple oData-service methods

Hello!
I am a JavaScript developer and I have never worked with SAP/ABAP. I need a simple service to test my SAPUI5 apps. Please help me to create a test oData service based on table.

I created a simple table ZSTUD_USERS, add a data into table, activate it. Then I add a methods, register a service, activate it.

I test in /n/IWFND/MAINT_SERVICE but I do not get the data in the browser.

Help me please write a getentityset-method to get the data from table based on this:

method ZSTUD_USERSSET_GET_ENTITYSET.

    SELECT * FROM ZSTUD_USERS.

  ENDMETHOD.

As well as how do I write the methods for create, update and getentity-method correctly?

Thank you!