What is the opposite of the following word?

Malo

The opposite of malo is simpatico/a or bueno/a/

Explanation: Malo is an adjective for bad in spanish and simpatica means nice and bueno means good. So it honestly just depends what you are describing in the sentence.

ah, so ustedes and nosotros are my 'go-to' if i am using spanish mainly in the states? interesting, but still slightly confusing, haha."

it seems that you are a little confused about subject pronouns. yo=i, tú/usted=you, nosotros=we, ustedes=you(plural), ellos/ellas=they.

in the case of vosotros, it is an informal replacement for "ustedes" in spain. similar to using "you all" in english.

even though it is not generally used in conversation outside of spain, it is used many times in literature. i would suggest having at least some familiarity to that form, at least to recognize what it is.