a GuestAnother method would be to add an external link as a menu item directly to your page/menu at whatever position you require, but if you want to add a like button to a module position, simply install a good third party share plugin. like extensions.joomla.org/extension/facebook-like-and-… as an example. Hope this helps.
Facebook Like and Share button - Joomla! Extension Directory
Facebook Like And Share Joomla Plugin enable Facebook "Like button", the "Share This button", and the "Comment Box" on your published articles, with the following…