1. In the Microsoft 365 admin center, go to "Billing" and then "Your products" page:
Microsoft 365 admin center / Your Products
2. Locate and select the product for which you want to either get the license key or download link.
3. On the product details page, in the "Downloads and keys" section, choose the Product version, the Language, and the CPU & file type, then select "Download" to download the installer.
4. To download the key when required, select "Show activation keys". Then from the right side window, select "Copy key to clipboard". Paste the key in a text file or a note app in a secure location and enter it as instructed during the software installation. The key is needed to activate the downloaded software.