You can force all of your pages to use HTTPS. To do this you will need to modify your .htaccess file. First, connect to your website via an FTP Client or navigate to File Manager in your Control Panel. Using a code (text) editor, add these lines to the beginning of the .htaccess file.
RewriteEngine On
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://example.com/$1 [R=301,L]
Substitute example.com with your domain name.
If an .htaccess file does not exist, you can create one in your root directory.