1) One of the blogs which clearly explains how to use ODATA with an example
https://shootax.blogspot.com/2019/10/d365fo-data-integration-by-odata-part-1.html
2) How to solve the error "The natural key for the table was not found in a data entity"
https://d365ffo.com/2021/06/28/ax-d365fo-how-to-solve-the-error-the-natural-key-for-the-table-was-not-found-in-a-data-entity/
3) Custom Workflows in D365: Step-by-step procedure to add a new workflow.
Custom workflows in Microsoft Dynamics 365 for Operations – Dauvis' Dev Musings
If we are struck on opening the workflow with "Forbidden" error then open the cmd prompt in admin mode and run the following command, restart the aos services
rundll32 dfshim CleanOnlineAppCache
4) Creating a module in D365:
5) Excellent blog contains all modules
https://organicax.com/category/microsoft-dynamics/