餐馆, 饭馆, 酒家, 饭店 - restaurant in Chinese?
They all mean restaurant, but a little difference:

餐馆 is normal, not so big, but formal restaurant.

饭馆 is smaller, and casual restaurant.

饭店 is bigger restaurant with higher qualification, be able to perform ceremony such as wedding.

酒家 is an ancient word which means a kind of restaurant providing liquor. Nowadays used for the name of restaurant for antique flavour.