I’m actually not sure what to check for watt consumption. I’m only seeing volt and amp.

So I have a LCD mirror, with a controller board. And I’m planning to get a raspberry pi to run magic mirror 2 on. But I would like to make this as clean as possible. And the included power supply for the controller board is bulky and and the power supply is in the middle of the cord like normal. But I’d like it inside mirror without a large bundle of cord (The goal is to keep it thin). Also I’d like to only run one power cord to the mirror, if seen cheap step down module’s and think that may be the best way? Any advice is appreciated!