Hello KazuT,
Thank you for reaching out to the Microsoft Community! I’m really sorry to hear you’re having trouble with your One drive. Let’s see what we can do to sort this out, OneDrive Online does not currently offer a built-in feature to prompt for a password every time you open a new tab to your OneDrive homepage. Once you're signed in to your Microsoft account in the browser, OneDrive remains accessible until you sign out or clear session data.
But you can do is use a separate user account on the computer, Create a dedicated macOS user profile for yourself. This isolates your browser sessions, OneDrive access, and files from other users.Go to System Settings → Users & Groups to add a new user.
or use OneDrive personal vault, OneDrive has a Personal Vault feature that adds an extra layer of security. Files stored in the vault require re-authentication (e.g., password or biometric login) even if you're signed into OneDrive. Great for sensitive documents like timecards or financial records.
Feel free to reply for better understanding.
Warm regards,
JayMark