Hello!
Welcome to the geek club!
I suppose you have developed your own hardware? (otherwise it would be configured out of the box and
you wouldn't ask).
I have no experience with PIC, but at a first glance, I would bet PGEC and PGED are the correct ones.
OSC pins are oscillator (crystal) pins.
Now second glance, if you look at the documentation (you can search the PDF for "PGEC"), you will find
an explanation page 25 of what it does. It says it's the programming clock, so it's safe to assume that it's PGC.
That said, you might consider buying an evaluation board which will ensure that everything is configured
fine. Getting some experience in programming before developing your own hardware is probably better
than starting everything from scratch.
Dora