Site within a site?

Hello. Our organization would like to create an environment where individual towns (groups) can post their own content. In order to do this, we need to create an environment where each group can have its own static WP page, then make their own blog posts and connect their own social media and have it visible from their page but retain editing access to only their content. The options are overwhelming and I can’t find a solution that specifically allows this. Has anyone encountered, and solved, this situation?