Use Mac mini as a server
The most popular server features—File Server, Time Machine Server, and Caching Server—are a part of macOS, so it’s easy to use your Mac mini as a server. Open System Settings, then click Sharing to access one or more of the options below.
File Server: Uses File Sharing to allow users to store and share folders and files on Mac mini. See Set up file sharing on Mac in the macOS User Guide.
Time Machine Server: Uses File Sharing to allow users to back up their Mac computers on your Mac mini using File Sharing. See Back up to a shared folder with Time Machine on Mac in the macOS User Guide.
Caching Server: Uses Content Caching to provide caching of software distributed by Apple through the internet. See Change content caching settings on Mac in the macOS User Guide.