How do I secure a page within my site so only club members can access this portion of the site?
There are some 3rd party widgets for "only" login but even the inventors do admit that these are not 100% safe. Passwords are accessible from code of the site.
You would need a CMS
You might have a look here: https://musewidgets.com/collections/widgets/external-cms
Publiz is recommended sometimes for different purposes, maybe also for what you want to achieve.
Here you will find maybe what you need.