WHERE IS? Access control settings for the community

Summary:

Can someone please help me figure out where this is or if maybe we have it hidden in a customization? I cannot find where to manage access control for a community beyond defining the communities visibility when searching. We're experiencing issues with Required Members in our Communities and their access to courses in the catalog (even with the checkbox stating to have the community define access). Where do we define access?

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Version (include the version you are using, if applicable):

23D Redwood UI

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