Why use a Child Theme in WordPress?
WordPress is just so great to build a responsive website. With the latest variety of devices to view web pages, we need a platform that can render our sites in various screens.
There are many themes to choose from in WordPress. You can choose here https://wordpress.org/themes/ depending upon your needs. But in using these themes, it is advisable to use a child theme. Because developers often update their themes for some additional features or check and remove bugs. You don’t want your site to show broken codes especially when you made some changes with the php or css files. Click here to read the codex of how to make a child theme, https://codex.wordpress.org/Child_Themes.
You can use this plugin https://wordpress.org/plugins/child-theme-configurator in setting up a child theme. The plugin is just so great.
All the functionality of the parent theme will be copied to the child theme. You can freely manipulate the new child theme according to the needs of your website.