1) wsusou is designed to install security relevant updates onto a target machine. In your case a Windows 7 one.
viewtopic.php?f=7&t=172You have to configure UpdateGenerator to download the updates for Windows 7. Then copy the client-folder to the target system (it is unimportant, how you do it) and run UpdateInstaller and follow its instructions (!).
2) wsusou does not download or install any driver (see the referenced topic from above). You have to manually install them (Driver DVD, Internet research, Windows Update; that would be the order I'd use).
3) Which apps are you talking about? Windows 7 just supports Win32 executables, not the new ModernUI apps. Please tell me, what you want to install. I'll try to help you with it, even if it is off-topic as it is not concerning wsusou directly.
4) Files stored on the device: if you formatted the HDD, everything is wiped. No file is left and (if you did it the correct way) cannot be restored. The format-command cannot be undone.
Wer Rechtschreibfehler findet, darf sie behalten oder an den Meistbietenden versteigern. / Everybody finding a misspelling is allowed to keep or sell it.
aker
WSUS Offline Update „Community Edition“
https://gitlab.com/wsusoffline/wsusoffline/-/releases