Hi,
Thank you for posting your question in the Microsoft Community.
Sorry to know that you are facing this issue.
Unplug all external devices connected to the computer and check if there is progress in the upgrade. If there is no progress then restart the computer to get to the desktop screen.
You may want to download the ISO file and save it to the USB flash drive using the media creation tool.
Installing Windows 10 using the media creation tool:
http://windows.microsoft.com/en-us/windows-10/media-creation-tool-install
Keep us informed to help you further.