Windows 10 can hang for up to 24 hours when installing, at any stage of the process.
Approximately how long have you left it for at 99%?
Ok, you need to leave it loading and don't disturb it for up to 24 hours - it should complete within that time.
I have accepted your request for remote assistance
Can you go to www.teamviewer.com
Click on Download in the middle of the page
Download and install the program and give me the ID and Password ***** please so I can connect
Do not close the program but leave it open else I will not be able to connect