"Even" has two meanings. The first is simply "equal." "Even" is used as a qualifier in sentences to amplify the meaning of a word. For example, "What do you mean?" means you don't understand their meaning. "What do you even mean?" has the same meaning, but you are especially confused. Another example, "If you go, I won't stop you." It means that you won't stop someone if they leave. "Even if you go, I won't stop you." Even, in this case, amplifies the sentence to make "if you go" seem like a last-resort.