Hi there and welcome
Sorry to hear about the issues you are experiencing.
To remove windows 10 and revert back to your previous version, open the Start menu and select Settings. Click the “Update & security” icon and select “Recovery.”
You should see a “Go back to Windows 7” or “Go back to Windows 8.1” option. Click the Get started button to get rid of your Windows 10 install and restore your previous Windows install.
Once complete it will then be reverted.
I can also do these steps for you, and have made a request via Additional Services. This is optional, and if you choose to do this, I can, with your permission, remote into your computer while you watch and do all these steps (and deal with any problems that arise during them) for you. Or if you do not choose to take this service, we can continue here. This is no problem at all. Just let me know please.
Else let me know the results please.