Add this code in below within .htaccess file
RewriteRule ^(.*)$ index.php?/$1 [L]to
RewriteRule ^(.*)$ index.php/$1 [L]based on the example urls your provide. http://url.lar/index.php/about/ doesn’t have a question mark in it after index.php
It is also possible that mod_rewrite is not enabled. It looks like you are an a Debian based system such Ubuntu. You can use the command
sudo a2enmod rewrite enable mod_rewrite