Why do I get "you have connected two terminals of different types"

[Kyle97330]

You're trying to put in a cluster of arrays, but what you need is an array of clusters of arrays:

Graph is simple.

For XY, each cluster there is an array of X points and their corresponding Y points.  So if they share X coordinates, for instance, you can just fork that wire into the first element of the clusters.

Also just as a note you are replying to a thread from about 20 years ago....