even though I have the product code showing that I own a a unique copy of Windows I cant install it back.
Can you explain this a little more? Where is the Product key Showing? If you are trying to type in he product key for an Dell Laptop, the product key is for an OEM version of Windows. If you are trying to install a Retail version it will not accept your OEM Product key.
Follow the instructions in the link in Post
#2. Download the ISO image for Windows 10 and burn the image to a USB Flash Drive using the
Media Creation Tool on the same site.
Put the freshly burned Flash drive into the Dell Laptop and Start the computer pressing the
F12 key continuously. You should be presented with the One Time Boot Menu, where you would select your Flash drive to boot. You now should be booting from the Flash drive. In the Windows Installer, choose your Language. Then choose
Custom Install. In
Where to Install Windows. Delete
All Partitions on the New HDD, if any, until the disk is all
Unallocated Space. The press
Next. Windows will create partitions and Format them during the install. It shouldn't ask for a product key, but if it does just click
I do not have a product key at this time. At the End of the install it shouldn't need it but if it asks for a product key to activate. type in the OEM product key that is on a sticker on the bottom of the laptop.