Fuchsia target devices must be connected to a host device via a network link. SSH is the protocol for communications over that link, as described in this document.
Getting the Fuchsia device address can be done using ffx.
The unit of installation on Fuchsia is a package. For information on how to push packages to a Fuchsia device, see the this document.
In order to retrieve logs from a device, open a shell on the device and run the log_listener command, which provides various filtering knobs. See this page for more details.