Check your usage under Settings > OneDrive Settings > More Settings > Storage Metrics.

Yes, but you'll need the OneDrive desktop app installed on your computer. This app syncs your OneDrive files to your device, enabling offline access. To make specific files or folders available offline, right-click them in File Explorer and select Always keep on this device. Any changes made while offline will automatically sync to OneDrive once you're back online. Visit Microsoft’s detailed guidance for step-by-step instructions on setting up the app.

If you delete a shared file you own, it is removed for everyone. Other users will no longer have access unless it is restored from the Recycle Bin.

Yes. Right-click a file, select Version History, and restore from a list of available versions.

Personal Microsoft accounts (e.g., Outlook.com) and institutional accounts like your CMU Andrew account operate in separate environments. If someone tries to share a file from their personal OneDrive with your Andrew OneDrive, the sharing settings might block access due to organizational restrictions.

For details on how sharing policies work across different account types, refer to Microsoft’s guide on external or guest sharing in OneDrive, SharePoint, and Lists.

OneDrive does not allow direct transfer of files and folders. If you wish to give the files to someone else, you first need to share the content with them and have them create a copy on their drive. Note: This may cause a loss of file metadata, such as comments or timestamps.