What does est-ce que tu veux mean?

used at the beginning a question.

Est-ce que tu viens ? will you come ?

Est-ce que tu aimes les chiens ? Do you like dogs ?

Two ways to ask question (grammaticaly correct)

Est-ce que + suject + verb

or

Verb + subject

Do you like dogs ? = Aimes-tu les chiens ?

You can contract in (popular form)

T'aimes les chiens ? you like dogs ?