First make sure you have added both English and Spanish as content languages - see http://docs.composite.net/HTML/C1-Localization/Website-Languages.
For help on how to translate pages see the user guide on Multiple Languages in Composite C1.
To get a language switcher see http://www.composite.net/Add-on-Market/Packages/Composite.Navigation.LanguageSwitcher.XSLT/UserManual
For help on how to translate pages see the user guide on Multiple Languages in Composite C1.
To get a language switcher see http://www.composite.net/Add-on-Market/Packages/Composite.Navigation.LanguageSwitcher.XSLT/UserManual