Can someone explain to me how a PG year works and the benefits? I guess similar to what Pannell did.

With Boarding it cost’s $57K to attend Deerfield, he then used this as a spring board to Cornell, Ivy league which doesn’t offer scholarships. Financially, do the families cover the full cost of PG with the expectation of an IVY education? I understand there are grants etc to help out with the tuition at Cornell but $57K is a lot to absorb just to get there. Anyone familiar with how the PG avenue works?