Here is how you can draw sketches in Life is Strange 2 and get the Sketchy Achievement / Trophy. Right at the beginning of the game you can go into your room and sit down in the red bag.
Sean takes out his sketch book and you can look up to look at your room. Hold A/X to observe the room and look down again to draw. You can do this by wiggling the left stick in any directions.
After Sean observes a second time and draws in the book, the sketch is done and you unlock the Sketchy Achievement / Trophy.