Preposition “à”:
In English “à” can be “to”, “at”, “in” and sometimes nothing (I go home)
The preposition “à” is contracted with the masculine definite article in French
Je vais à la plage: “plage” is feminine, no contraction.
Je vais à l’école: “école” is feminine but we don’t mind; the word starts with a vowel so “à l'”.
Je vais à l’étage: “étage” is masculine but again we say “à l'”.
Je vais à l’hotel: same thing for words starting with a plugged “h”
Masculine:
Je vais au cinéma ( we don’t say “à le” but “au”)
J’ai mal au pied (my foot hurts)
Plural:
Je vais aux toilettes (toilettes is always plural in French from France)
“Aux” works with masculine and feminine words.