Asklemmy

I am not a lawyer of any kind. The wiki does say:

"Many civil law systems, which are common in Continental Europe, Latin America and much of Africa, impose a far more extensive duty to rescue.[3] The duty is usually limited to doing what is "reasonable". In particular, a helper does not have to substantially endanger themselves.[23]

This can mean that anyone who finds someone in need of medical help must take all reasonable steps to seek medical care and render best-effort first aid. Commonly, the situation arises on an event of a traffic accident: other drivers and passers-by must take an action to help the injured without regard to possible personal reasons not to help (e.g. having no time, being in a hurry) or ascertain that help has been requested from officials."

To apply this to your question, my interpretation is that if you come across a car accident and nobody is there, and you have some first aid training, you should first call emergency services, and then render as much aid as you reasonably can without endangering yourself. If the car is teetering on a cliff about to fall over, I sure as heck wouldn't jump in. If the driver was ejected from the car and they are bleeding to death right in front of you then you should probably do your best to stop the bleeding if you can I guess. If the driver looks like they sustained heavy injuries and the car isn't about to explode or fall of a cliff, then I would just hang out until an ambulance gets there because I wouldn't want to break their neck moving them. Idk though, not a lawyer or a doctor so who knows.

Basically if you see a car accident, and there is either an ambulance there or there are already people stopped, you are supposed to drive along and not impede anyone or join a leering crowd. If they need your help, they will wave you down.

If you see for example an upturned or crashed car that no one is around, you are supposed to:

• Stop safely. If you can't, stop where you can and call emergency services.
• Use the emergency triangle in your car to indicate a possible road hazard at least 50 meters in advance.
• Determine if there are any personal injuries, even suspected (if someone fell from a motorbike or was hit by a car, maybe got a concussion, don't let them continue driving), with proper triage. First concern is life-threatening injuries, then lighter injuries, disregard people who are obviously dead or not going to survive. "Not going to survive" means missing major parts of body, "not breathing" is obviously life-threatening, but that's why you know CPR.
• While doing the first three, call emergency services as soon as it's feasible, start the call with your position, then describe the event, in particular the number and kind of injuries, then tell them your name for reference.
• Start first aid as you can, and follow the instructions of the emergency services.

At least that's what the driving license exam has you train for.