You manage parent sites the same way as the default site. Select the parent site in the Sites & settings treeview. On the Tasks tab, you design your site from sections such as Pages & templates, Parts, and Friendly URLs. On the Settings tab, you select site-specific settings such as languages to support, registration and login options, and whether to use reCAPTCHA for payments.
For information about how to create a site, see Manage a Parent or Child Site.