Congrats with your Leningrad, seems you got a fine example with a good lens. What needs to be adjusted is the rangefinder cam which couples and moves with the lens, second is the mark for infinity. (Its a screw hidden under the screw of the front rangefinder eyepiece.)
In such way that camera and lens focus correctly at 1m and infinity. The distance of 1m is measured from the object towards the back of the camera.