The drivers for this modem are actually located inside the modem's storage. The installation should start automatically when the device is inserted in a USB port of the computer. If the installation does not start automatically, you can browse the storage drive (it's listed as removable drive in My Computer).
If the device still does not get detected, you will need to install the corresponding software then use Device Manager and manually update the driver pointing the installation window to the Huawei folder from Program files.