Hi Camille! I know you can disable the user list in the admin settings. Look for “enable user directory”. Then you can access the user list from the admin dashboard.
I don’t know how to hide the about page. Are you sure you want to remove that? It is fairly important to provide a place to see the contact email address for the site. That’s also how people find their way to the terms of service and privacy policy.
I do know you can use CSS to remove links from the hamburger menu - not sure if this is up to date but you can try it: