Windows 10 allows you to download the Operating System Software. This is a big change for the way Microsoft distributed the installation disks. You may need this to perform a system repair. Here is a link to the download.

https://www.microsoft.com/en-us/software-download/windows10

Another link we often need is for the Windows Update Catalog. Here you can search for the appropriate update. There is often a listing for a 32-bit version and a 64-bit version, so be careful of which one you download. Here is the link.

http://www.catalog.update.microsoft.com/

Lets us know if this helped you.