You've probably hearing a workaround solution on it, where a folder is being shared to people or probably an account where the password shared by different people. But in the product design, there's no such thing as shared OneDrive.
You could consider SharePoint Online, that is designed for document collaboration, while a personal OneDrive is targeted at individuals. You would be better off moving those files to a SharePoint document library (or many document libraries if you wish to separate them logically) rather than storing them in OneDrive.
Once the files are in the document library, users can use the "Sync" button in the library to access the library from their desktop (Windows Explorer) using the OneDrive for Business desktop app.
Sync SharePoint files and folders
The other solution to this, definitely is Microsoft Teams. As the name suggests, it's designed to store files, work conversation, and whatnot, shared to only a small group of people. The backend side of things is still using SharePoint Online. So, administrator does not need to worry about missing legacy files after the account is deactivated (due to resigning or any other reasons).