Install CI for local site with WAMP

Hi, I'm beginner to use framework and a bit confuse. I want to upgrade an existing website ; I download the full website with FileZilla and edit on local with WAMP.

I installed CI on local site (as it was a plugin) so in wamp64\www\SiteName\CodeIgniter. Does it the right place or should have been place at the same level of SiteName (so wamp64\www\CodeIgniter) ?
I even wonder if in fact the CodeIgniter folder shouldn't be rename as the SiteName and merge the both folder. What should I do to start using it properly ? Thanks.

CodeIgniter should be your sitename.

Example:

ci3testing (Project Name)
-- application
-- system
-- public or public_html
---- index.php ( Edit to the application and system paths ../application and ../system)
---- all other file with index.php

What did you Try? What did you Get? What did you Expect?

Joined CodeIgniter Community 2009.  ( Skype: insitfx )

Thanks a lot InsiteFX for the clarification.
I think, imho, Installation Instructions's page can be improved by adding that point. Because I was really confuse from where I should place my just extracted CI fresh folders from my existing projects in order to not impact them all (and avoid eventual collateral damage) but at least impact the good one.