A yes/no question needs no extra word and no change of order - the same sentence with rising intonation is the question, written between ¿ and ?. For anything else, open with a question word: qué, quién, dónde, cuándo, cómo, por qué, cuánto. Every one of them carries an accent.
Examples
- ¿Hablas inglés?
- Do you speak English?
- ¿Cómo te llamas?
- What is your name?
- ¿Dónde vives?
- Where do you live?
The mistake to avoid
The upside-down ¿ is not decoration - it opens every question in writing, and leaving it out is a spelling mistake.
Where this fits in
Greetings & introductions, Spanish A1: Say hello, give your name, ask someone else's, and where they're from.