Duolingo can be so very picky about matching word order sometimes, and then it gives us this one, where the English and Chinese sentences don't really match semantically... this is what I get for trying to work without the word bank
The 很 is there for grammatical reasons. The sentence structure noun is adjective (e.g. the cat is sad) needs "很" as "is". It is then not necessarily understood as " very". If you want to express someone is very cute, use 非常 or 真
Often times 很 is used like "is" in English. 我很好 is closer in meaning to "I am fine" than "I am really good." If you want to really stress something you can use the word 非常 (fei chang) to mean "very" or "extremely."