What does 'te' mean
It is a personal pronoun, and in both of the sentences you used, it is a direct object pronoun. Answer to your question: The word "te" always refers to "you" informal, or in a friendly manner or situation.
So for your examples,
te amo: the "amo" means "I love" and the "te" means "you". So you get "I love you"
Same generally concept with "te quiero" this is just more of a friendly type of love. (I think, natives please correct me if I'm wrong.)
Spanish just puts the object pronouns in front of the verb (most of the time, but there are exceptions) instead of behind the verb, like we do in English.
Here is a "Spanish 1 understanding" of the basic layout of a Spanish sentence...
Subject + no (if necessary) + Reflexive, Direct object, and Indirect object pronouns (in that order) + verb + everything else.
Sorry, that is probably more info that you wanted. It just seemed like it would clear up any confusion that would later arise. Hope this helps
Te can be a direct, indirect, or reflexive pronoun for 'you'. In this case, te amo means 'I love you', with te being a direct object pronoun. For more information on these pronouns check out these reference articles by clicking on the links below.