what does 'como es' mean
Welcome to the forum!
The question is incomplete, in my opinion. It translates into "How is?", using the verb ser.The common question "¿Cómo está (usted)?" means "How are you?", but the use of "es" doesn't make sense to me.
For example "¿Cómo es el libro que estás leyendo?" = "What is the book that you are reading like?" (or "How is the book that you are reading?")
Note that this is quite different from "¿Cómo está tu madre?" ("How is your mother?") The latter asks after the condition/state of the person. Whereas, the former asks "What kind of book is it?" (or whether it appeals/pleases).
The same distinction applies to the (even more similar) sentences: "¿Cómo está tu primo?" and "¿Cómo es tu primo?" The first asks after his health/state of being while the second asks what kind of person he is (tall/short, cheerful/pessimistic, etc)
mmmmm you need to add something else to it to even make it a complete sentence and depending on the rest of the sentence it could mean something different.
Como es? How is?