Studying abroad does not mean you will learn English magically. Many people think that they just need to live in another country and they will learn the local language. This is not completely true. You still need to pay attention and study. There are people who live in foreign countries for many, many years without knowing the language well. However, it will probably come to you easier and faster than if you just studied the language in your home country.
Studying abroad can be hard. You will probably have times when you miss your family, friends, food, and everything familiar. Almost everyone goes through some culture shock. You will have to realize and accept that it will take some time to adjust to a new way of living.