To display different information within your sidebars, top footer area or main footer area you will need to configure your widgets.
To setup widgets this can be done in Appearance > Widgets.
On the left, you will see all the widgets that are available for you to use, and on the right you will see all of the different widget locations.
As an example if we wanted to display a custom menu within the third column in our main footer area. We can drag a “Custom Menu” over from the left, into “Footer Column 3” on the right, and set the menu up here.