Before you throw your router out the window or call your ISP, there is one software fix that solves 80% of mysterious Wi-Fi issues:
Wi-Fi Keeps Dropping? Here’s How to Properly Reinstall Your Wireless Driver reinstalling wifi driver
Reinstalling forces Windows to rebuild that translation layer from scratch. Most people uninstall the driver and panic when the Wi-Fi disappears. Don't worry. Here is the safe way to do it. Before you throw your router out the window