The new MinRole server idea is cloud inspired and prioritizes in managing the server roles instead of the services.
The available server roles are Front-end, Application, Distributed Cache and Search.
Every server role must be designed on its server and can’t be combined with a second role.
So you will need at least 4 SharePoint servers to a Multi-Server farm when initializing MinRole.
You can also choose for a custom role where you can configure the service as per your needs. The final role is the Single-Server farm which runs all SharePoint services on one server