newton first law
an object that stays at rest would stay at rest and an object they stays in motion will stay in motion till some type of unbalanced force is acted on the object.
why you should wear a seatbelt and why it represents newtons first law
you should because if you don't you will get hurt. it represents newtons first law because if you crash into like a tree without a seat belt you will still be going the same speed till something stops instead when you do have a seat belt you will stop.
what this picture shows
this picture shows a person driving fast and crash without a seatbelt and fly out of the car going the same speed which represents newtons first law because it does represents inertia and he goes the same speed tilln some unbalanced force stops the object.