Ordered quantity in Header

Hi

I have a small question ..

I have in an order header the quantity : "example 1000" BUT we receive this order on several delivery lines: "example 4 lines"

In my fact table which is at the level of the delivery line, how do I manage the quantity ordered?

Do I keep in my fact table in quantity ordered: 1000 on the 4 lines and in the PBIX I make an average indicator of the quantity ordered?

Or do I create in the pbix in dax an indicator that only displays the quantity ordered (1000) for the first line of the order? (like that if I look at several different commands I'm right too?)

Or does it put in the fact table 250 in quantity ordered on each line so that I can make a sum in the PBIX ?

I don't know what is the best practice for this case...

Thank you in advance for your help