Petri 7s - 35mm Film Camera

This is the first film camera that I fell in love with shooting 35mm film - when I first came across it I prayed day and night to be able to find a functioning number to be able to shoot with it and finally after two purchases I got myself a working body that comes with a 45mm fixed lens rangefinder style. The camera was first introduced to public in early 1960s and it truly gives all the vintage vibes, however when shooting it I could not make head or tail out of the focusing ring as you have to overlap a shadow of the subject you see on the viewfinder over the subject itself . . .  which I clearly had no clue how the line up works, neither framing a 45mm lens because more than half of the images on the roll came out of focus. Since then I have not had a chance to play with it again but hopefully soon I get to try a second roll of film on it to test it out again.