Index.html to index.php in ubuntu

How to do the same same thing in ubuntu apache2.
I tried but unable to find files similar to centos I found the folder sites-enabled and DocumentRoot /var/www/html
but unable to find index.html any where coud someone help me here with out .htaccess

Kindly clarify more the scenario you try to apply to help you properly as you can set the path /var/www/html as a DocumenRroot in apache2 also.

I was talking about index.html to index.php I was unable to find any code mentioning that index.html is the root document as like in httpd i as able to to achieve this with .htaccess that to redirect the traffict to index.php
but my question is how to mention in apache2 files that my root document is index.php

@bonthusaireddy , You can mention it using Directory Index in the apache configuration or using htaccess file.

Ok Thank you
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