sun and pluto in conjunct.Azazel astrology it says that in this case the father will die prematurely or it may make the father obsessed.
yes i am obsessed with my father and he has a big importance in my life.
a friend of mine has this aspect and he lost his father.

i'm scared of this situation what can i do to prevent it?My father's natal charts is uncertain so I can't look at his natal chart.

This is a contingency, not the fixed rule. "Death" cannot be stopped.

Put an aura of protection on him.