After a Windows update to my surface book, I lost all wifi and wireless options, including hotspot. After I share my pain, I do have a solution simpler than anything posted that I have seen. After spending three hours on it myself last weekend, I went to the Best Buy Geek Squad who said check back in 10 minutes. After 15 minutes, I was told they would need two days. They When I picked it up, it still did not work. They sold me wifi adapter for about $40 and sent me on my way. When I got home, the instructions said "download a driver", except I had no way of accessing the internet to download a driver. Back to Best Buy. They substituted a wifi adapter that did not need a driver dowloaded. Back to the house. Indeed, I had internet access thru my wireless system. But, my computer had now audio. Back to the Geek Squad. This time their "best guy worked on it. And now for the solution....
He discovered that the update turned off wifi and audio, and he had to go into BIOS and turn them back on. Then, everything functioned normally. I did not need the wifi adapter (refunded me the money), and I had all audio functions back. So......
Before you try other in depth fixes like reinstalling your Operating System, find the BIOS settings and turn your wifi and audio back on.