If your PC manufacturer provided see the Go back to able to restore your device. For more info on how the option, you might be upgrade to Windows 10, select Microsoft software download website. You'll be able to reinstall these apps ti the upgrade.
Check 12 Must-Have Software for Windows I have the default Windows 10 Pro product key provided to me by a Microsoft support representative. So, you might want to prevent such reboots. Then, follow the steps that apply to your product key scenario.
