The public_html directory is your webroot directory. By default your website is loaded from public_html folder. If you create a website under a sub-folder and you want to display it when you type the domain name, add the following lines to your .htaccess file.

Replace domain.com with your domain name. Replace folder with the folder having your website.

Incase there is no .htaccess file you may create a new .htaccess file using filemanager in cpanel.