В чем разница между a cat и a puss и a pussy и pusses ?Пожалуйста, приведите примеры.

“Cat” is the standard name for the animal, it can refer to any kind of cat.

I don’t really hear “Puss” very often anymore, but it also refers to a cat (like “puss in boots”). It’s short for “pussycat”.
It can also refer to a young girl (Old English), or a face (“sour puss expression”).

(“Pusses” is just the plural form of “puss”.)

“Pussy” is also short for “pussycat” but nowadays is a derogatory term that refers to a vagina (but it also means weak or cowardly)
Example: You’re being a pussy right now, just do it.