Hi,
For enterprise version, which have install the latest update package for keep system version latest.
For LTSC version, which will not install update frequently to keep system stable.
So, I would recommend to install Windows 10 Enterprise version, after installed it, update it through Settings\Update & Security\Windows Update to keep system latest. And then perform a full scan with Windows Defender.
If you think your One Drive has get infected, you could restore to previous version on One Drive to the day before get infected. Restore a previous version of a file stored in OneDrive
For details about get infection on One Drive, please refer to: Ransomware detection and recovering your files
For activation with subscriptions E5, I am afraid there is no trial version for it. But for details we could contact with local sales partner or volume license support. Without activation evaluation, we also could use the Windows Defender to scan disk.
Microsoft Licensing Activation Centers worldwide telephone numbers
Bests,
============================================
If the Answer is helpful, please click "Accept Answer" and upvote it.
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.