What is the right Joins in Web Reports Gen 2 to have On Hand Inventory and Order fulfilment

As a business we want to have a visibility of what it's been allocated towards the orders and how much is my actual on hand in WMS to be able to make decicions, we want to have this information on the same report, but looks like the categories and joins are impossible to get merge and have the right information, is there a way to do this? or someone that knows how ?