The first thing you would want to check is how much the snapped key is stuck inside the ignition. If you think you can pull off the key in the ignition, then you can use a needle-nose pliers to carefully take it out. Once you’ve removed the stuck key, make sure to go directly to your trusted automotive locksmith or car dealer to get a replacement.
You may be tempted to twist the stuck key inside the ignition to try and turn on your car, but if it doesn’t go well, you may end up breaking another portion of the key. This will result in a smaller key size stuck in the ignition in which you won’t be able to get it out. When this happens, you will definitely need to call an automotive locksmith to help you with the situation.