"What is my name?"
Translation:Quid est mihi nomen?
This really should be "Quod" and not "quid". I know that Plautus used "quid," but Terence and many others after used "quod". It also makes more grammatical sense based on the classical era distinction between Quid and Quod (which obviously was after Plautus' time, but still forms the basis of our current conception of "correct" Latin grammar).
You will also notice many modern textbooks using "Quod" instead of "quid, for exactly these reasons.
Correct classical Latin is "Quod est mihi nomen?" NOT "quid."
Quod = Interrogative adjective that is modifying the noun "nomen;" the expression could be rewritten "Quod nomen est mihi?"
Quid = the interrogative pronoun, and cannot correctly be used in the expression to ask for a person's name.
Meus, mea, meum are possessive adjectives (which the English uses: "my"). In Latin, we use mihi for the dative of the pronoun "to me". The structure of the sentences is different in the two languages. (I see you also study Spanish. In spanish you say "I am called..." In Latin it's, "what is the name for you")