That action means “post the form back to the website root”. Your website root is the very ‘top level’ of your domain, for example http://www.example.com/.
The hash indicates the point in the document to jump to – in this case, I’m betting the ID of the form is wpcf7-f1-t1-o1?
You shouldn’t need to alter this. Even though the form is on a page outside of WordPress, when the user clicks submit, they’ll get sent back to your homepage where the form can be handled.