Yesterday, Microsoft released Windows 10 build 14915 for PCs and phones to the Fast ring. There were four known issues listed for the PC build, but not the one that would affect Surface Pro and Pro 2 users, which is that it seems to break Wi-Fi.
First discovered by Windows Central, it's unclear how many users are having this issue, as Microsoft hasn't yet commented on it. We upgraded a Surface Pro to test it out, and sure enough, it resulted in the screenshot that you see above.
If you've got a Docking Station and use a wired connection, you should be unaffected by this, although we haven't tested it out. If you can't get on the Internet at all, your best bet is to roll back to build 14905, which you can do by heading over to Settings -> Update & security -> Recovery, and click "Get started" under "Go back to an earlier build". Rolling back is always a bit of a dodgy process, but it's your best bet on getting your Internet back into a usable state.
Once you roll back, you might want to turn off Insider Preview builds for the time being. You'll have the option to do this for 1, 3, 5, or 7 days.