To backup a WordPress site for free, you will first need to install the UpdraftPlus plugin. To do so, open your WordPress dashboard, and select Plugins > Add Plugins from the menu bar. Then type UpdraftPlus into the Search Bar. Select the UpdraftPlus WordPress Backup Plugin and click Install Now > Activate

You can mannually

To backup a WordPress site for free, you need to take a manual backup. Download WordPress files and folders from File Manager on cPanel, or via FTP; and then export the WordPress database from phpMyAdmin. Some web hosts include backups as a part of their hosting package, so check with your web host if this is the case