01) Access your Administrative Panel www.yoursite.com/wp-admin
02) After login click on Appearance >> Widget
A widget is a block or module that can be inserted into your site to offer some feature or perform some particular function.
Widget areas are spaces created by the theme author where you can add one or more widgets. These areas are usually sidebars, areas in the footer, an area before or after the text of a post, in specific pages of the site etc., the number of areas and their locations depend on the author of the theme that created them according to the style or Purpose of the topic.
The widgets available in your installation can be seen in Appearance »Panel Widgets. On the left side of the screen are the Widgets available and on the right side of the screen, the widgets areas of your theme.
WordPress has standard widgets like to show a list of recent posts, comments, search form etc. In addition, some themes and plugins can add other widgets to your installation.