Will Windows Obtained From Microsoft Recognize Dell's License?

Your XPS 9520 will come with either Windows 10 or Windows 11. Even if you wipe the drive, even if you replace the drive and install Windows on a new drive in the same laptop, your system will still be licensed.

When you use Microsoft's Media Creation Tool to create a bootable flash drive with Windows installer and then perform a new Windows install, your licence will automatically activate once connected to the Internet. There is no need for special installation media from Dell, and in fact they likely no longer provide any since you can always download from Microsoft.

I know because that has been the way it works since at least Windows 8.1.

As long as you don't replace a major component such as motherboard or CPU, it will reactivate. And if you need to do that, you may still be able to get it activated by contacting Microsoft. There is a Microsoft web page for Windows activation issues on which you fill out a form, and then either you call Microsoft or they call you (I forget what the sequence is), and they are quite helpful.

Here's a Dell manager explaining it, where he writes: "The product keys are embedded on the motherboard and sometimes associated with your Microsoft account (if logged in with your Microsoft account). This means if you need to reinstall Windows 10, it will get automatically licensed."