First, read the English article below.

Click the Windows logo in the bottom-left corner of the screen. Click the gear-shaped icon in the left-hand side of the Start window. This circular arrow-shaped icon is at the bottom of the Settings window. It's a tab on the left side of the window. You can do this in one of two ways, depending on whether you have to buy a key or already upgraded for free on a different computer:   Free Upgrade - Click Troubleshoot, enter your Microsoft email address and password if prompted, click Activate Windows, and click Activate when prompted.  Purchased Key - Click Go to store, click Buy below your preferred version of Windows, and enter your payment information. Click Start, click Power, and click Restart. Once your computer finishes restarting, your version of Windows should be activated. 

Now, please write a short abstract for it in Vietnamese. Abstract:
Mở Start. Mở Settings (Thiết lập). Nhấp vào Update & security (Cập nhật & bảo mật). Nhấp vào thẻ Activation (Kích hoạt) ở phía bên trái của cửa sổ. Kích hoạt bản Windows của bạn. Khởi động lại máy tính.