So, everybody has forgotten or didn’t see the blink and you’ll miss it shot of those ancient Jedi books stashed away on the Falcon? Rey may not have a living trainer, but she’s got the instruction manuals.
I vaguely recall a scene of her closing a drawer I think aboard the Falcon with I think books or paper of some sort inside though I didn’t take particular notice of the drawer contents. I do understand though that this is the shot you speak of and do remember it to an extent.
I’d hardly call them instruction manuals though. As I understood it, they were at most dogmatic preachings, stories and histories of the first Jedis, not a step by step instruction manual on how to master the force.
Plus Yoda says “there’s nothing in the books that the girl rey doesn’t already know”.
Which means she can then learn nothing from the books, yet clearly she is still untrained in the conventional sense and as expected in the SW universe. These new movies simply expect you to take it as they show you and not question anything or relate it to what you already know from the OT. It’s actually one of the messages in TLJ - don’t question what you’re told Poe, just do as you’re instructed and blindly trust the new leader (ie. Disney).