Short answer, you cannot update Windows 10 directly without an Internet connection.
Update Windows 10 Without Internet Connection
However, if you have an Internet connection on some other PC, you can get the information of latest update (I mean note down the number which is in the form of KBxxxxxxx) from the following link.
https://support.microsoft.com/en-us/help/4055254
Download the update. Transfer the update to Windows 10 PC and install it by double-clicking the file.