SharePoint Online is a cloud-managed file storage solution, where users can share, manage and collaborate on documents in real time. A file server typically stores them on your onsite network, or an offsite data-Centre in some cases, where SharePoint Online stores your files in the Microsoft cloud. SharePoint Migration is a free tool provided by Microsoft and works great to migrate existing File Server, on-prem SharePoint Server to the SharePoint Online. Below are the to download the tool, setup and migrate your data successfully