Here are the steps you can take to properly delete a WordPress site.
Step 1: Backup Your WordPress Site
The first thing you need to do is to create a complete backup of your WordPress site. Even though you want to delete your site completely, you should still make a backup. This will come in handy in case you change your mind in the future, or want to access a piece of content that you had already deleted.
Step 2: Delete Your WordPress Files
Now you need to delete WordPress files stored on your server. Deleting these files will erase WordPress software as well as your themes, plugins, images and other media files.
You can do that by visiting your WordPress hosting account’s dashboard. Upon login, locate the File Manager icon. File Manager provides a web-based interface to manage files stored on your server. You need to go to the /public_html/ directory and delete all WordPress files stored there.
You can also delete your WordPress files using an FTP client instead of using the File Manager within your control panel.
Step 3: Erasing the WordPress Database
Although the software is no longer there, the database still remains. So, let’s remove it as well to uninstall WordPress thoroughly. Navigate to the MySQL Databases section and locate the name of the WordPress Database. Click on it to expand a drop-down where you can select Delete.
Keep in mind that it is important to delete installs of WordPress you no longer wish to use. Outdated installations of WordPress leave you open to the possibility of malware or exploits.