If you’re making an RPG, I’d guess you’d not only want this information persistent across level changes, etc., but also between play sessions, right? If so, you’ll probably want/need to create a save directory and write the information to some kind of a data file every time you/the player saves. Then, once the player loads/reloads in, recreating and storing that information possibly in gameinstance or gamestate.
Disclaimer: I haven’t had to do or consider the second part of your question, so this is just based on my understanding of persistence in UE and what I’ve read.