I failed my exam because of windows 10

I can appreciate your frustration. You can have considerable control of Windows updates if you know how, and avoid all those problems.

How can you get such information? Research it (e.g. Google); use the Tutorials here; search the forum here- where I've posted this sort of info a number of times.

Here's how:

1. Set Active hours to prevent automatic restarts during normal working periods

That's a widely documented Windows feature. Unfortunately off by default.
Enable or Disable Active Hours for Windows Update in Windows 10 Windows 10 Windows Update Activation Tutorials

2. Set updates to 'Notify' so you neither download nor apply updates unless you approve them.
That's much less known.

How? By any of these methods:
a. Using Winaero's free tweaker (convenient)
b. If you have Win 10 Pro using the Group Policy editor
c. If you have Home - by using a registry edit or reg file.

Tutorial: (includes Notify)
Enable or Disable Active Hours for Windows Update in Windows 10 Windows 10 Windows Update Activation Tutorials
Either Option 1, 4 or Option 2 4

And finally if you have Pro you can set Defer Feature Updates
- which means you can delay major build upgrades.

There are further time delays available via the Group Policy Editor (Pro).

This is a timely reminder of how important it is to keep backups of important documents and not just on a drive on your computer but preferably externally.

As noted above, set active hours so that can at least mitigate it while you're working.

You can also schedule restarts after updates: