Article in English: Click a product such as Word or Excel to launch the program. If you own a product key but don't have Microsoft Office installed on your computer, you'll have to use the Office website. It's below the icon with an image of a key. It's in the "Activate" option. Type the 25-digit product key without the dashes. It's in the box labeled "Add this key to an account". If you already have a Microsoft account, sign in with email address and password associated with your Microsoft account.  If you don't have a Microsoft account, click "Create a new account" and follow the prompts to create a new account. Your activation is now complete and the product key is tied to your Microsoft account.

Summary in Chinese:
点击Office产品。 点击激活。 点击输入产品密钥。 输入产品密钥并点击继续。 点击联机兑换。 点击登录或创建新帐户。 点击完成激活。