clone a site wordpress

Can anybody tell me how to clone a WordPress site with all plugins exactly how it looks...

Most WordPress website are themed customize, you can identify the theme by seeing the codes

You mean, cloning a website you own? (Easy)
Or cloning a website that's not yours? (Scraping)
For option 1, I always use the free plugin All-in-One WP Migration , it's as simple as effective!

For option 2, I don't know...

If it is your site
--------------------
You can install Duplicator Wordpress Plugin on your site and build a package that you can copy to other host and install. So you will get exact site duplicated. This is used for site migration purpose.

If it is not your site
------------------------
Use to check the theme and plugins used on the site. Though you can not clone, you can setup same looks. Owner of the site may have changed the Theme name, in that case you can look in the source of the page to get the hint. Not all plugins used by the site are shown by the detector.