After installing the FileViewer Managed Package, assign specific users the FileViewer Permission Set and grant each user a FileViewer License through Setup -> Installed Packages -> FileViewer -> Manage Licenses.
Create custom fields on the Content Version Object for File tagging.
Configure Lightning Record Pages on the objects where FileViewer will be used to Tag & Upload Files.
Optionally, use the Configuration Fields within the FileViewer Lightning Components to control default values, end user experiences, custom labels, and more.
For more details on Configuring FileViewer, see the Quick Start Guide.