The preinstalled OS is ready to be configured at the appropriate point when you first apply power to the server. Review Required OS Patches and Package Updates to find out if the preinstalled OS requires package updates.
You can reinstall the OS and install patches instead of using the preinstalled OS. See Minimum Supported Versions of the OS, Firmware, and Software.
Refer to the Oracle Solaris documentation for instructions on installing and configuring the Oracle Solaris OS.