Learn Italian: Dove vai stasera? Vado da Luca. - Where are you going tonight? I am going to Luca's.

In Italian, when you are going to a person's house, shop, or workplace, you must use the preposition da. Since Luca is a person, vado da Luca translates perfectly to "I am going to Luca's place". If you were going to a city or a general location, you would use a or in instead.

Is stasera a combination of other words?

Yes! It is a shortened, combined version of questa sera (this evening). Over time, it became so common that Italians started writing it as the single word stasera. You will also see this pattern with stamattina (this morning).

Why does the verb change from vai to vado?

Both words are forms of the verb andare (to go), which is a highly irregular verb. Vai is the "you" form used for the question ("Where are you going?"), and vado is the "I" form used for the answer ("I am going").

Why are the words for "you" and "I" missing from the sentence?

In Italian, you usually drop subject pronouns like tu (you) and io (I). Because the verb forms change for each person, vai always means "you go" and vado always means "I go". The verbs themselves already tell us who is doing the action.