There are two ways to say you in French! In general, you use tu in friendly conversations or with kids. You can use vous to address more than one person, but also in formal situations or with adults you don't know.
Tu aimes le vin ?
Doyoulike wine?
Madame, voyagez‑vous avec votre fille ?
Ma'am, areyoutraveling with your daughter?
Madame, voulez‑vous du café ?
Ma'am, doyouwant some coffee?
S'il te plaît vs. s'il vous plaît
Just like the difference between tu and vous, s'ilteplaît is more informal while s'ilvousplaît is more formal!
Votre passeport, s'il vous plaît ?
Your passport, please?
Tu veux un peu de sucre ?
Do you want some sugar?
Oui, s'il te plaît.
Yes, please.
Literally, both expressions mean if it pleases you!
Which what is which?
To ask a what or which question, you'll use quel if the noun is masculine and quelle if it's feminine.