No, cats do not fear death. The reason is straightforward. Cats are not self-aware by which I mean self-conscious. Some people will dispute that statement. I’ll proceed though. As they are not self-aware when they are in pain or discomfort due to a chronic illness which is killing them or a sudden trauma and injury which is ultimately fatal, they don’t recognise the fact that they might die soon.

They recognise the pain that they feel and the emotional anxiety, and also that as a consequence they are vulnerable to predators. This process is completely instinctive as often for a domestic cat there is no real risk of being attacked by a predator.
When a cat feels pain they probably instinctively consider themselves to be under attack but they can’t see the source of the danger and therefore can’t defend themselves.
They therefore decide to hide to protect themselves and find time to recover. As long as they feel pain they sense that they are under attack and don’t come out. But while they do this they die but without understanding that they are in the process of dying. It is a beautiful way to die rather like a sudden hear attack for a human.
Cats have no fear of death. This is a clear advantage over humans who live with this fear all their lives. Provocatively I’ll say that this is one reason why we have religion and spiritualism. We need to anaesthetise ourselves against the unpleasant feeling of anxiety that one day we will die. We pretend that we go to another world, a better place without pain.
In many ways humans have become too intelligent because it plays tricks on us. Our intelligence makes us self-aware which potentially brings a multitude of mental health issues to us.
P.S. This is a personal viewpoint and I am happy to read about alternative ideas in comments. Good comments will be incorporated into the article.
SOME MORE ON SELF-AWARENESS:
Nice comment. I guess the truth is we don’t know if cat’s fear death or understand the concept of death. One day we probably will. My article is a guesstimate based on my current gut feelings about this.
I remember our cat who one day went to each room in the house and contacted each member of the family for a short time, and then went out and never came back. two d ays later we found his dead body under the neighbour’s hedge.
it really did feel like he was saying goodbye to each one of us.