Yea but if your never born, then you don’t go back to kill your grandmother since you wouldn’t be born meaning you will be born to go back and kill her meaning that you won’t be born to go back and kill her, and it just infinitely repeats
Technically, time travel is impossible because if you go back in time and kill your grandma it means that your mother will never be born and if your mother will never be born than you can't be alive so you can't be doing time travel
