what lol, sorry for being mean but next time put a question as your title, i only clicked this post cuz i am just reading every new post, yap i have no life.
now to you question
wordpress is by far the easiest install and adding plugins or themes works the same
in your worpsress folder you have a folder called wp-content here you have themes and plugins
lets say you download a theme unzip it and you want to use it, well just upload the theme in its folder, to the wp-content/theme folder
than under the design tab in your wp-admin you can activate your new theme
same goes for plugins only, they are uploaded to the wp-content/plugins folder and activated through the admin link called plugins, quite easy don't you think?