If you have many files, 5GB of storage may not be enough with the free account. In the future, instead of continually making transfers manually, remember that within the application, you can always save files directly into the OneDrive folder. Or you can select the files and use the "Move to" option available in the "Home" tab of File Explorer. You can always cut and paste the files into the OneDrive folder. Of course, this is only one way to upload files.
Once you complete the steps, the files and folder in the OneDrive location will automatically sync to the cloud service in the background. Drag and drop each file and folder you want to upload to the OneDrive folder (left).
You can download the OneDrive client offline installer from Microsoft (opens in new tab) and double-click the file to install it. Quick tip: If you do not find OneDrive on the Start menu, the client is probably not installed.
Once you complete the steps, you can connect the account to Windows 10 and start using OneDrive.