Start as naoe and push through activities like shrines and temples to hit knowledge rank 1, that's when the grappling hook opens up in the shinobi path. Get familiar with lb/l1/q to launch and b/ctrl to drop since you'll be using it constantly for climbing. Good to know the hook works best when you chain swings together, and mastering the timing lets you grab those tricky achievement points without touching ground.

Once you're comfortable swinging between points, try mixing in some jumps for faster movement across rooftops especially during missions. Tip you might find interesting is dumping some mastery points into the shinobi path makes the hook way more versatile later on. Just keep an eye out for those marked grapple spots while exploring, they show up pretty clearly against buildings and cliffs when you're in range.