How to Create an Efficient One to Many Data Entry Form in Blazor

I have seen the online demo using the Northwind Database, I found out that doing a one to many data entry like entering an Order and Order details is inefficient or not user friendly because the end user will first create an order header then save it, then after go to order details and select everytime the order header or order number before entering the order details, is there an example on how to efficiently collect invoice data like the one on Northwind? (Order and Order Details)
Thanks very much!

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