If you are installing Windows 10 (or reinstalling it) then this may be the issue. Sometimes when it is being installed/reinstalled/updated it gets stuck. It happens if any of the files that are trying to be installed/updated don't work correctly. Then the system keeps trying to do it, over and over. Getting you stuck.
Try this.. If you are connected to the internet via Ethernet, unplug. If you are connected to the internet via WiFi, you need to either turn off the WiFi access (turn it off on router/modem), turn off the router/modem or, if not possible, take the laptop somewhere there is no WiFi. Then turn off the laptop and restart it. While there is still no internet at all. It should load all the way through. Then once it is up and running again, you can reconnect to the internet.