You should now have a fresh new WordPress install ready to log in to.
Multisite
If you want to create a multisite install, use the wp core multisite-convert command:
wp core multisite-convert --title="My New Network" --base="example.com"
Importing Content
You may have content you want to pre-add or migrate to your new install. For this WP CLI provides the content import and export commands. These commands accept or create standard wxr files, the same format used by the WordPress export and import plugin in the admin interface.