Hello Emre Öztürk,
Thank you for posting in Q&A forum.
Is there a Group Policy I can enable to prevent them from adding work accounts or not?
A: Based on my knowledge, there is no Group Policy to prevent adding work account. It seems that as soon as the account is logged in to Windows and Teams, this account will appear under Settings\Emails and accounts\Accounts used by other apps.
You can try to set and let one specific account to sign in one specific machine.
For example:
User1->PC1
User2->PC2
User3->PC3
it stays open on the computers, and they see each other's documents.
A: You can block they store data on local disk, and you can create one shared path and create one folder (named using their user account name), only one can access one own folder.
For example:
User1->Access User1 folder
User2->Access User2 folder
User3->Access User3 folder
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best Regards,
Daisy Zhou
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