The staff is friendly, but speaking English is not a common skill. Many branches including Shibuya and Shinjuku. Make sure you understand the price range of a restaurant before you enter. Restaurants that appear similar on the surface could have amazingly different costs. Also make sure you know the prices of what you are ordering.
Restaurants can be very expensive.
However, there are many small and inexpensive eateries. Noodles of all types are popular and usually cheap. Some are stand up places. It is considered polite to slurp noodles. Restaurants with a red paper lantern in front serve ramen.