To force traffic to use the HTTPS protocol, the most common method is to implement request redirection through the .htaccess file, the following is a basic description of the .htaccess file and the procedure:
.An .htaccess file is a simple text file with the name “.htaccess” that contains additional settings passed to the web server that can support some of the more complex features of a website.
If you are using a script created by someone else (including a content management system such as WordPress), you can usually find an existing .htaccess file in your website's htdocs folder; if you don't already have one, you will need to create it yourself - it is recommended that you use a file manager to create one! This is because some systems (especially Windows) do not support .htaccess files well, and a file manager can help you avoid problems during the creation process.
Once you have found or created the .htaccess file, you can edit it using a file manager, or any text editor (e.g. Notepad), by adding the following lines of code to the file:
RewriteEngine On
RewriteCond %{HTTP:X-Forwarded-Proto} !https
RewriteCond %{HTTPS} off
RewriteCond %{HTTP:CF-Visitor} ! {"scheme": "https"}
RewriteRule (. *) https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]Source : https://forum.infinityfree.com/docs?topic=49322
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