I would agree it is quite easy Unlike, say, 3.X to PF things are different enough that you won't be tripped up by the temptation to just assume you know how things work, and the system overall is quite standardized and easily explained. Really pretty much everything is different and listing it would be futile, but in terms of "big picture" changes the largest are probably Bounded Accuracy and Advantage/Disadvantage.

Bounded Accuracy is a philosophy of tightly controlled bonuses, so everything stay closer to within the d20 throughout the levels. Stats soft cap at 20, "proficiency" (BaB/Skills/Saves) goes from +2 to +6 instead of +1 to +20 (or 3-23 or 2 to 12). This means when you are fighting dragons a fair sized group of bandits can still be a meaningful encounter, and no matter how high level a bad roll means you can still lose the village chili cook off to a lucky random.

Advantage/Disadvantage replaced many modifiers to rolls. Where previously you might have gotten a +2 morale bonus and a -4 penalty from a curse, you get "advantage" (roll 2d20 keep highest) or "disadvantage" (keep lowest) on a roll. If you have both you roll normally. It trades some granularity for ease. You don't have to track as many modifiers, but an attack by a cursed squeezing blind frightened heavily exhausted poisoned Fighter is no worse than one that is just poisoned, and one source of advantage would bring either attack to neutral.

Other things you'll probably notice are archetypes being baked into classes and backgrounds covering the area traits did (without the balance issues and nonsense like "Accelerated Drinker"). Magic has vastly changed, working more like Arcanists and heavily using concentration to limit buffs. Feats are an optional system and tend to do much more without long chains or stiff prerequisites. Also... I should stop myself, because again, pretty much everything is different. The basic rules are free here, check them out. It really isn't hard to get going and well worth a try to see if it fits you.