Enfold theme: Learn how you can install a WordPress theme from ThemeForest, create a child theme, and import one of its ready-made demos. This tutorial gives you step-by-step instructions to create a website from scratch, which otherwise would cost you some money. For your reference, please check the link below to download the child theme.
This can be used with any other themes too by making some basic changes. Moreover, this tutorial is not limited to enfold themes, you should be able to do it with other themes as well. The process is very similar – possibly the demo importing portion may vary but you should be able to workaround. Hope this WordPress tutorial is useful.