This page presents the OGC API resource paths as an HTML tree.
The tree currently represents a mix of CubeWerx stuff (e.g. the "schema" paths) and OGC stuff (both officially specified and under development).
Associated with each path element, in square brackets, is an indication of the operation that each HTTP method might perform at that end point. Again, this is a mix of speculation and specification.
There is also an extended version of the OGC API resource tree that incorporates the concept of the data store which is a CubeWerx concept but is logically equivalent to a DCAT dataset and can be found here.