Controls
Moving/Looking
Holding the "Zoom" trigger moves the camera into a first-person view, which can be controlled using either the D-Pad or Analog stick. This allows Ryo to "lock on" to items of interest, so you can pick up or otherwise interact with the item.
Looking around
You can look around with the analogue stick, and the R-trigger moves the camera to a first-person perspective. The first-person perspective allows Ryo to "lock on" to objects he is able to interact with - this is often the best way to select exactly what you want to interact with if there are a number of items to choose from.
Fighting
D-Pad: Move
A: Kicks
B: Throws
X: Punches
Y: Dodge
L-trigger: Run
R-trigger: Stored move (during fights) / Move scroll (when practicing)
There are dozens of moves that can be performed - see the Move Scroll for a complete run-down. Some moves cannot be performed before they are "learned" in-game - either taught to Ryo by other characters, or when you find or buy a Move Scroll.