How to change footer information?

 
After theme installation of footer section on the front-end, you will see standard demo content. This content is included in theme files. To change it or remove at all from the footer you need not change theme files.  It can be easily changed through your admin panel . You need to enter  Appearance > Widgets. On the left side you will see the widget areas list with footer areas included.

To clear the areas  – add an empty Text widget. To display your content, you need to add necessary widgets into appropriate footer  areas.