In English, we say we’re going to the city or the countryside, but we live in the city or the country. In French, you always use en with ville and à la with campagne.
Jusqu’à and à can both mean to! To say that you went up to a place but didn’t go inside, use jusqu’à. When you want to say that you went to a place and then went inside, use forms of à.
J’ai marché jusqu’au restaurant.
I walked to the restaurant (but didn’t go in).
Je suis allé au restaurant.
I went to the restaurant (and had a meal!).
To say how long you do something, use pendant.
J’étudie avec Duo pendant vingt minutes tous les soirs.
I study with Duo for twenty minutes every evening.
Tu as attendu ta sœur pendant une heure ?
You waited for your sister for an hour?
Mes amis ont voyagé en Europe pendant deux semaines.
My friends traveled in Europe for two weeks.