Sign in to OneDrive in Windows
When you sign in to your Windows 10 or 11 PC with your Microsoft account, OneDrive is already activated by default.
Or if you prefer, you can sign in to OneDrive itself (separately from Windows’ sign-in) with a Microsoft account. On the notification area of the Windows taskbar, click the OneDrive icon (it looks like clouds with a slash over them), and click the Sign in button. You’ll be guided by the OneDrive notification app to sign in with your Microsoft account. (If you don’t see this icon, it’s probably hidden on your taskbar. Clicking the upward pointing arrow should reveal it.)

Signing in to OneDrive in Windows.
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This guide refers to how OneDrive functions when you sign in to OneDrive for Windows with a Microsoft 365 business account. But most things are the same if you use a free Microsoft account.
Store and sync files and folders to OneDrive in Windows
When you open File Explorer, OneDrive appears in the navigation pane on the left. You interact with it like any regular storage drive connected to your PC: You can put your files or folders in it by dragging and dropping them from another location, or by saving a document, image, or other file type to it from an application.

You can access OneDrive files and folders in File Explorer.
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When you put a file or folder into your OneDrive, it is synced to the cloud. If you delete a file or folder in your OneDrive, it’s deleted from the cloud as well.
If you change a file or folder and save it in OneDrive, the new version will replace the older version stored in the cloud. If you’re offline when you make changes, the newer version of the file or folder will be synced to the cloud when your PC connects to the internet again.