If you face this issue, running troubleshooter can most probably resolve it but since you have reached this page, you most probably have done that already.
So what you can do now is to go to Services app and turn off
- Background Intelligent Transfer Services
- Cryptography Services
- Windows Update.
Next, run the troubleshooter again and this time, SKIP fixing 'pending updates' and just fix the database corruption.
Once you see that the database if fixed, you can proceed to update using Windows ISO which you can download from here instead of using Windows Update app.
If you face the following issue during the update then you need to download Windows 10 1909 which you can do that by using Rufus.
Once you have updated to 1909 successfully, then you can continue to use Windows Update app to update your Windows.
I will add the graphics when I have the time.