Thank you for the info! That is helpful!
I checked my logs - apparently it is an issue with Apache configuration? "AH01630: client denied by server configuration - "A common error when accessing localhost via a browser. See possible causes and solutions, such as updating Apache 2.4 configuration, checking access rules, and fixing DocumentRoot path."
I am going to try and use a walk-through of how to troubleshoot that error. If I get stuck, I'll post where I am still confused. I'll update, for sure, if I am able to fix the problem.