There are a few ways to buy genuine Windows 10:

• From the Microsoft Store. This is the most direct way to buy Windows 10, and it ensures that you are getting a genuine copy of the software. To buy Windows 10 from the Microsoft Store, go to the Microsoft Store website and select Windows 10.
• From authorized retailers. Authorized retailers, such as Amazon, Best Buy, and Walmart, also sell genuine copies of Windows 10. When buying Windows 10 from an authorized retailer, make sure that the retailer is reputable and that the software is sealed in its original packaging.
• From your PC manufacturer. If you are buying a new PC, you can also buy Windows 10 from your PC manufacturer. Most PC manufacturers offer Windows 10 as a pre-installed option on their new PCs.

To make sure that you are buying a genuine copy of Windows 10, look for the following:

• The Certificate of Authenticity (COA). The COA is a sticker that is located on the bottom or back of your PC. It contains a unique product key that you will need to activate Windows 10.
• Genuine Windows packaging. Genuine Windows 10 software is sealed in its original packaging. The packaging should have the Microsoft logo and the Windows 10 logo prominently displayed.
• A digital license. If you are buying Windows 10 from the Microsoft Store or from an authorized retailer, you will receive a digital license. This license is linked to your Microsoft account and allows you to activate Windows 10 on any compatible PC.

If you are unsure whether or not you are buying a genuine copy of Windows 10, you can contact Microsoft customer support for assistance.