1. I usually buy waffles from the cart on the road near Seowon Market.
2. Walk from the school gate toward Chungrryeol Apartment. The restaurant is between the bookstore and the post office across from the apartment.
3. Go out of the school gate. Turn left. Go straight for two blocks, and you can see Chungryeol Apartment. The cart is on the road next to the stationery store.
4. Go out of the school gate. Turn to the left. The restaurant is next to the stationery store. The restaurant sell doughnuts and sandwiches. A jam doughnut is 50 cents. A cake doughnut is 1 dollar. You can also buy drinks and pretzels. A drink is 1 dollar and a pretzel is 2 dollars.
(Would you check the short passages? Correct any errors, please.)
1, 2, and 3 are perfect.
In 4, you need "sells" (restaurant is singular). Everything else is fine.