Playing with WP without damaging non-WP site

I’m just learning how to use Wordpress and want to install it on my existing site, which was designed by someone else, without benefit of WP.

The one-click WP install asked me to confirm that there were no other files under my domain, but of course there are, so I didn’t install it.

Can I create new sub-folder, install it there, play with it until I’ve got something I like and then move it up?

Thank you!

Yep! You can also do this: