So I was in my home doing nothing but making some updates to my wifi network when my sister came and something happened between my sister,mother and I my sister 17 year old and me 13 year old went out in a quarrel she called me a psychopath and she said to me "I will slap you in your face I will poison you and kill you she also went on to tell my mother that I will never be seen agin meanning that she will kill me and no one will no what happened help me this is not a joke I am felling weird!
There is about a 99% chance she is being dramatic. Sibling rivalry can be intense.
However, this needs to come before the attention of a parent or trusted adult. It is bullying--big time.
On the 1% chance that you feel your safety is truly threatened, and a parent is not being helpful, you might call the authorities (police). You just described the legal definition of assault in America (but not battery). At 17, your sister could be charged with a crime.
Either way, she may benefit from counseling. My understanding is that some Asian cultures have a different concept of mental illness and mental health care in general, but it seems this is pretty straightforward. I'm not sure what kind of services would be available but perhaps a teacher can help.