Thank you for providing those details. We suggest creating Windows 10 installation media to help you with the issue that you are experiencing. To do that, please check this article. Download the Media Installer of Windows 10 and perform a boot. Choose Repair this PC then Startup repair. This method is quite different from the one that you’ve already performed using the Windows Recovery Environment.
After that, we suggest using the System Update Readiness tool (DISM) to help you fix Windows update errors. This will fix corruption errors that happen due to fail installation of Windows updates and service packs. Please refer to this article made by one of our MVP ZigZag3143 (MS -MVP) and follow the steps on how to perform DISM.
If you need further assistance, don't hesitate to reach out.