SEO questions

I did a site for someone who had WP installed already and handled the graphics for them…so I don’t know how accurate this information is. I would like someone to tell me their opinion on if any of these things make sense to you.

Do the page url’s matter in regard to SEO? The way WP is set up, URL’s have extensions like “?page_id=10” does this really matter for SEO? If so, is it worth the trouble of changing them all and how do I go about doing so?

Furthermore, is the wordpress installation is in a folder off of the domain name such as https://www.yoursitehere.com/home/ does this affect SEO or hurt it in any way? If that is the case, how would I go about removing the home folder and get it back to the root directory without re doing everything?