Hello, I am very new to this program and to PF 2E, so I apologize if this is a basic question.

I am using FG Unity and have a Paladin setup, and I have purchased the book, and the Lost Omens players expansion. I do see Lost Omens options for other characters and ancestries (races), but I can't figure out how to pick a "Last Wall" archetype for this Paladin? Is there something I need to do in the program?

Thank you.