mac os sierra upgrade
MacBook Pro with Retina display, macOS Sierra (10.12.6)
That is an update that can only be installed if you already have macOS High Sierra on your mac.
You can only upgrade to High Sierra via the App Store, click on Featured. This will download and install the full macOS High Sierra (5Gbs) and it will be version 10.13.1.
What mac do you have, what OS are you running.
What do you want to achieve?
mac os sierra upgrade