Some questions about the movie "No Country for Old Men"

I watched a movie named called¹ 'No Country for Old Men', my questions are as follow: Is Llewelyn planning to kill Anton by utilizing using² his wife? What meaning does the director want to convey at the part of³ when the Sheriff drops in on the man in his house where that seems isolated and occupied by cats? What does it is the meaning of the last conversation between the Sheriff and his wife (Loretta, I'm not sure if she is his wife)? Why did the traffic accident happened to Anton in that way condition, as we know he is so calm and crucial careful from the front part beginning of the movie?⁴

If my writing is not so fluent, please help me revise it. Thank you first.

1. “named” is not wrong here but “called” is far more commonly used.
2. Again, “utilizing” is not wrong here but this usage would sound odd to a native English speaker. “Utilizing a resource” in a technical discussion would be okay but here stick with “use”
3. This is unnecessary and makes the sentence sound awkward.
4. I wasn’t entirely sure what you wanted to express here so I have made as few changes as possible. Ideally I would change it a little more but it would be difficult to make further revisions without a clear idea of what you wish to convey.

I saw the film probably 5-6 years ago so I can’t remember all of it in detail but I will attempt to answer your questions:
No, I don’t think at any point Lleweln Moss tries to kill Anton Chigurh by using his wife. However, you could say, for the sake of keeping the money, he puts her life at risk. Chigurh promises Moss him that his wife will not be harmed if he returns the money but he refuses.
I remember the meaning of the last conversation was subject to much debate when the film first came out. I won’t regurgitate it all here. In a very simple sense, the Sheriff is reflecting on his own mortality in a violent world, perhaps resigned to his inability to change much and that it has no place as one of the “old men”. The story him losing the money his father gave him could be a reference to Moss, a person, in some sense he was “given” to look after but, ultimately, lost. This is probably simplifying it slightly but perhaps the DVD commentary (if there is one) can shed more light on this.
Cats, sometimes appear in murder films as silent observers. However in this case perhaps you are expected to reflect on the cost and sacrifice involved in police work (this makes more sense with reference to the last scene of the film that you also asked about).
As I have said I earlier, I don’t know if I have interpreted your question as expected but what I think you are asking is how someone as calm and collected as Chigurh could get involved in traffic accident like the one we witness towards the end of the film. I don't think Chigurh does anything to cause this accident through negligence or careless. It was simply another car failed to stop at a red light and then smashed into his car. This is just plain misfortune and, sadly, probably happens in America (and almost everywhere else in the world) every day.