OneDrive is really just an alias for a networked drive that points to a cloud location and is baked into every instance of Windows. Most OneDrive instances are for personal computers and they’re inaccessible to everyoen else. But you can manually share files.
SharePoint is a flexible enterprise website and fileserver for an organization to customize.
Teams is a Slack ripoff that allows employees to create teams with channels within those teams, and freeform chats. It also has a filesharing component to it.
It is awful to work around the half-dozen ways to store and share files. Really. Microsoft needs to unfuck this.