Dynamics 365 Project Operations leverages the technology/product called Project for the Web. But there are two versions of this product, one is the solo Project for the Web SKU and the other is Project for the Web embedded inside Dynamics 365 Project Operations. For simplicity, we will call them D365 PO and P4W!
Even thought P4W ‘powers’ D365 PO it does not mean that every single feature from P4W will show up in D365 PO. Why? because D365 PO requires more metadata to provide enough information for financials, and actuals in order to feed ‘any’ ERP system down the line and the current native integration with D365 F&O.
Now, if you end up on this page, https://project.microsoft.com you will notice that records created inside P4W, and D365 PO display with their respective logos (as below) so they can be both used side-by-side, but generally speaking that is not the normal usage.


This is how they both compare at the time of writing (green means yes and blank not supported):

Dynamics 365 Project Operations official documentation link: https://learn.microsoft.com/en-us/dynamics365/project-operations/project-management/create-wbs
Microsoft Project for the Web official site: https://support.microsoft.com/en-us/project
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Thank you and see you next time with more Dynamics 365 Project Operations hacks!